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How a monopoly ISP refuses to fix upstream infrastructure

The issues described in this article were resolved after this article was posted.

A documented case of infrastructure failure, failed escalation, and a company that refuses to investigate.

Here’s the situation: I have outages. My neighbor has the same outages. Xfinity won’t fix it.

I bought Xfinity internet in June 2024. Immediately, my connection started dropping. Multiple times a day. Every single day. After troubleshooting every piece of equipment I had and questioning my sanity my neighbor complained about the same thing which led me to understand this was not my equipment.

I set up an uptime monitor and found that these outages happen 6-7 times per day for 125 seconds.

Over 17 months of my service term that’s approximately 3,387 outage incidents totaling 117+ hours of cumulative downtime.

This outage pattern has recurred thousands of times. It is consistent, predictable, and it follows an automated schedule.

My neighbor has the same problem. Different house. Different line from a different junction box. Same 125-second outages happening at the same times of day.

PING Uptime Log
2025-11-21T14:42:31-08:00 Warning dpinger exiting on signal 15
2025-11-21T07:01:34-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 21.4 ms RTTd: 14.8 ms Loss: 10.0 %)
2025-11-21T07:01:28-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 21.7 ms RTTd: 15.8 ms Loss: 20.0 %)
2025-11-21T06:59:33-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.1 ms RTTd: 1.7 ms Loss: 21.0 %)
2025-11-21T06:59:28-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.1 ms RTTd: 1.6 ms Loss: 12.0 %)
2025-11-21T00:01:33-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 20.5 ms RTTd: 2.7 ms Loss: 10.0 %)
2025-11-21T00:01:28-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 20.6 ms RTTd: 2.8 ms Loss: 20.0 %)
2025-11-20T23:59:35-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 20.1 ms RTTd: 3.1 ms Loss: 21.0 %)
2025-11-20T23:59:30-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 20.0 ms RTTd: 3.0 ms Loss: 12.0 %)
2025-11-20T15:01:37-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 21.3 ms RTTd: 3.9 ms Loss: 10.0 %)
2025-11-20T15:01:31-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 21.4 ms RTTd: 4.1 ms Loss: 20.0 %)
2025-11-20T14:59:36-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 21.0 ms RTTd: 3.9 ms Loss: 21.0 %)
2025-11-20T14:59:31-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 21.3 ms RTTd: 4.3 ms Loss: 12.0 %)
2025-11-20T13:46:40-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 20.4 ms RTTd: 2.9 ms Loss: 10.0 %)
2025-11-20T13:46:34-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 20.2 ms RTTd: 3.0 ms Loss: 20.0 %)
2025-11-20T13:44:38-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.9 ms RTTd: 1.7 ms Loss: 21.0 %)
2025-11-20T13:44:33-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.7 ms RTTd: 1.7 ms Loss: 12.0 %)
2025-11-20T12:46:37-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 19.3 ms RTTd: 1.2 ms Loss: 10.0 %)
2025-11-20T12:46:32-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 19.2 ms RTTd: 1.2 ms Loss: 20.0 %)
2025-11-20T12:44:39-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.2 ms RTTd: 0.9 ms Loss: 21.0 %)
2025-11-20T12:44:34-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.3 ms RTTd: 1.0 ms Loss: 12.0 %)
2025-11-20T05:16:33-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 19.5 ms RTTd: 1.4 ms Loss: 10.0 %)
2025-11-20T05:16:27-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 19.5 ms RTTd: 1.4 ms Loss: 20.0 %)
2025-11-20T05:14:33-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.4 ms RTTd: 1.2 ms Loss: 21.0 %)
2025-11-20T05:14:28-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.3 ms RTTd: 1.2 ms Loss: 12.0 %)
2025-11-20T03:31:34-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 18.9 ms RTTd: 1.3 ms Loss: 10.0 %)
2025-11-20T03:31:28-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 18.8 ms RTTd: 1.1 ms Loss: 20.0 %)
2025-11-20T03:29:32-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.3 ms RTTd: 1.6 ms Loss: 21.0 %)
2025-11-20T03:29:28-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.4 ms RTTd: 1.6 ms Loss: 14.0 %)
2025-11-19T20:01:32-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 18.9 ms RTTd: 1.2 ms Loss: 10.0 %)
2025-11-19T20:01:26-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 18.8 ms RTTd: 1.2 ms Loss: 20.0 %)
2025-11-19T19:59:34-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.2 ms RTTd: 2.2 ms Loss: 21.0 %)
2025-11-19T19:59:29-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.1 ms RTTd: 2.1 ms Loss: 12.0 %)
2025-11-19T16:31:36-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 20.2 ms RTTd: 2.7 ms Loss: 10.0 %)
2025-11-19T16:31:29-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 20.2 ms RTTd: 2.8 ms Loss: 20.0 %)
2025-11-19T16:29:35-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.6 ms RTTd: 2.1 ms Loss: 21.0 %)
2025-11-19T16:29:30-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.8 ms RTTd: 2.3 ms Loss: 12.0 %)
2025-11-19T13:31:35-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 17.7 ms RTTd: 2.5 ms Loss: 10.0 %)
2025-11-19T13:31:29-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 17.9 ms RTTd: 2.6 ms Loss: 20.0 %)
2025-11-19T13:29:38-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 16.7 ms RTTd: 2.0 ms Loss: 21.0 %)
2025-11-19T13:29:32-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 16.6 ms RTTd: 2.0 ms Loss: 12.0 %)
2025-11-19T10:31:39-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 19.6 ms RTTd: 1.4 ms Loss: 10.0 %)
2025-11-19T10:31:33-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 19.5 ms RTTd: 1.3 ms Loss: 20.0 %)
2025-11-19T10:29:39-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 18.9 ms RTTd: 1.2 ms Loss: 21.0 %)
2025-11-19T10:29:33-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.1 ms RTTd: 1.3 ms Loss: 12.0 %)
2025-11-19T03:46:32-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 19.6 ms RTTd: 2.6 ms Loss: 10.0 %)
2025-11-19T03:46:25-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 19.6 ms RTTd: 2.7 ms Loss: 20.0 %)
2025-11-19T03:44:33-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.4 ms RTTd: 1.2 ms Loss: 21.0 %)
2025-11-19T03:44:28-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.4 ms RTTd: 1.2 ms Loss: 12.0 %)
2025-11-18T22:31:36-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 19.9 ms RTTd: 2.6 ms Loss: 10.0 %)
2025-11-18T22:31:29-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 19.8 ms RTTd: 2.5 ms Loss: 20.0 %)
2025-11-18T22:29:34-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 20.1 ms RTTd: 2.5 ms Loss: 21.0 %)
2025-11-18T22:29:29-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 20.0 ms RTTd: 2.4 ms Loss: 12.0 %)
2025-11-18T12:19:41-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 21.1 ms RTTd: 4.2 ms Loss: 10.0 %)
2025-11-18T12:19:35-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 21.1 ms RTTd: 4.3 ms Loss: 20.0 %)
2025-11-18T12:17:42-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.5 ms RTTd: 1.7 ms Loss: 21.0 %)
2025-11-18T12:17:37-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.8 ms RTTd: 1.8 ms Loss: 12.0 %)
2025-11-18T12:16:37-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 19.3 ms RTTd: 1.6 ms Loss: 10.0 %)
2025-11-18T12:16:31-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 19.2 ms RTTd: 1.7 ms Loss: 20.0 %)
2025-11-18T12:14:38-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.1 ms RTTd: 1.2 ms Loss: 21.0 %)
2025-11-18T12:14:32-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.1 ms RTTd: 1.1 ms Loss: 12.0 %)
2025-11-18T09:31:37-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 19.4 ms RTTd: 1.0 ms Loss: 10.0 %)
2025-11-18T09:31:32-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 19.4 ms RTTd: 1.0 ms Loss: 20.0 %)
2025-11-18T09:29:38-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.6 ms RTTd: 1.3 ms Loss: 21.0 %)
2025-11-18T09:29:33-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.6 ms RTTd: 1.2 ms Loss: 12.0 %)
2025-11-18T07:46:33-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 21.1 ms RTTd: 15.0 ms Loss: 10.0 %)
2025-11-18T07:46:26-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 21.4 ms RTTd: 15.9 ms Loss: 20.0 %)
2025-11-18T07:44:32-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.7 ms RTTd: 2.1 ms Loss: 21.0 %)
2025-11-18T07:44:27-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.6 ms RTTd: 2.0 ms Loss: 12.0 %)
2025-11-18T02:46:34-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 19.0 ms RTTd: 1.5 ms Loss: 10.0 %)
2025-11-18T02:46:28-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 19.1 ms RTTd: 1.6 ms Loss: 20.0 %)
2025-11-18T02:44:33-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.0 ms RTTd: 1.0 ms Loss: 21.0 %)
2025-11-18T02:44:28-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.0 ms RTTd: 1.0 ms Loss: 12.0 %)
2025-11-17T23:01:33-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 18.6 ms RTTd: 0.9 ms Loss: 10.0 %)
2025-11-17T23:01:28-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 18.7 ms RTTd: 0.9 ms Loss: 20.0 %)
2025-11-17T22:59:35-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 18.8 ms RTTd: 1.0 ms Loss: 21.0 %)
2025-11-17T22:59:29-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 18.9 ms RTTd: 1.0 ms Loss: 12.0 %)
2025-11-17T17:01:35-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 20.5 ms RTTd: 3.3 ms Loss: 10.0 %)
2025-11-17T17:01:29-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 20.4 ms RTTd: 3.0 ms Loss: 20.0 %)
2025-11-17T16:59:36-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.4 ms RTTd: 1.5 ms Loss: 21.0 %)
2025-11-17T16:59:31-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.4 ms RTTd: 1.6 ms Loss: 12.0 %)
2025-11-17T13:31:36-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 20.1 ms RTTd: 3.3 ms Loss: 10.0 %)
2025-11-17T13:31:30-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 20.2 ms RTTd: 3.4 ms Loss: 20.0 %)
2025-11-17T13:29:37-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.3 ms RTTd: 1.1 ms Loss: 21.0 %)
2025-11-17T13:29:32-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.5 ms RTTd: 1.5 ms Loss: 12.0 %)
2025-11-17T12:46:37-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 19.0 ms RTTd: 3.4 ms Loss: 10.0 %)
2025-11-17T12:46:31-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 19.3 ms RTTd: 3.5 ms Loss: 20.0 %)
2025-11-17T12:44:40-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 17.8 ms RTTd: 3.1 ms Loss: 22.0 %)
2025-11-17T12:44:34-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 17.8 ms RTTd: 3.0 ms Loss: 12.0 %)
2025-11-17T02:46:33-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> none RTT: 19.8 ms RTTd: 2.6 ms Loss: 10.0 %)
2025-11-17T02:46:27-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> loss RTT: 19.8 ms RTTd: 2.7 ms Loss: 20.0 %)
2025-11-17T02:44:32-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: loss -> down RTT: 19.0 ms RTTd: 0.9 ms Loss: 21.0 %)
2025-11-17T02:44:28-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: none -> loss RTT: 19.2 ms RTTd: 1.5 ms Loss: 12.0 %)
2025-11-17T01:15:08-08:00 Notice dpinger MONITOR: WAN_GW (Addr: 8.8.8.8 Alarm: down -> none RTT: 19.0 ms RTTd: 1.1 ms Loss: 0.0 %)
2025-11-17T01:14:57-08:00 Warning dpinger send_interval 1000ms loss_interval 4000ms time_period 60000ms report_interval 0ms data_len 1 alert_interval 1000ms latency_alarm 0ms loss_alarm 0% alarm_hold 10000ms dest_addr 8.8.8.8 bind_addr 24.2.60.72 identifier "WAN_GW "
Event Log from My Modem
23:00:33
Sun Nov 23 2025 	 	Critical (3)	 	UCD invalid or channel unusable;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	Time Not Established
	 	Critical (3)	 	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
   	Time Not Established
	 	Critical (3)	 	UCD invalid or channel unusable;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	05:15:36
Mon Nov 24 2025 	 	Critical (3)	 	UCD invalid or channel unusable;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	Time Not Established
	 	Critical (3)	 	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
   	Time Not Established
	 	Critical (3)	 	UCD invalid or channel unusable;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	06:45:43
Mon Nov 24 2025 	 	Critical (3)	 	UCD invalid or channel unusable;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	Time Not Established
	 	Critical (3)	 	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
   	Time Not Established
	 	Critical (3)	 	UCD invalid or channel unusable;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	08:30:40
Mon Nov 24 2025 	 	Critical (3)	 	UCD invalid or channel unusable;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	Time Not Established
	 	Critical (3)	 	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
   	Time Not Established
	 	Critical (3)	 	UCD invalid or channel unusable;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	09:45:37
Mon Nov 24 2025 	 	Critical (3)	 	UCD invalid or channel unusable;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	09:54:45
Mon Nov 24 2025 	 	Critical (3)	 	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	09:54:51
Mon Nov 24 2025 	 	Critical (3)	 	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	09:55:29
Mon Nov 24 2025 	 	Critical (3)	 	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	09:55:29
Mon Nov 24 2025 	 	Critical (3)	 	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	09:55:30
Mon Nov 24 2025 	 	Critical (3)	 	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	09:55:30
Mon Nov 24 2025 	 	Critical (3)	 	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	09:55:37
Mon Nov 24 2025 	 	Critical (3)	 	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	09:55:37
Mon Nov 24 2025 	 	Critical (3)	 	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	09:59:51
Mon Nov 24 2025 	 	Critical (3)	 	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
   	09:59:54
Mon Nov 24 2025 	 	Critical (3)	 	UCD invalid or channel unusable;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	Time Not Established
	 	Critical (3)	 	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
   	Time Not Established
	 	Critical (3)	 	UCD invalid or channel unusable;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	Time Not Established
	 	Notice (6)	 	Honoring MDD; IP provisioning mode = IPv6
   	10:08:01
Mon Nov 24 2025 	 	Notice (6)	 	DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	10:08:03
Mon Nov 24 2025 	 	Critical (3)	 	UCD invalid or channel unusable;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	10:08:04
Mon Nov 24 2025 	 	Critical (3)	 	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	10:08:09
Mon Nov 24 2025 	 	Critical (3)	 	UCD invalid or channel unusable;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	10:52:13
Mon Nov 24 2025 	 	Notice (6)	 	CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
   	10:55:40
Mon Nov 24 2025 	 	Notice (6)	 	CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=00:40:36:86:90:ac;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;
Event Log from My Neighbor’s Modem
Date Time	Event ID	Event Level	Description
11/24/2025 10:44	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/24/2025 10:32	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/24/2025 10:17	74010100	6	"CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/24/2025 09:33	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 16:33	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 16:15	74010100	6	"CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 15:44	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 15:30	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 15:14	74010100	6	"CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 2.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 14:35	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 14:29	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 14:15	74010100	6	"CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 13:29	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 11:33	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 11:14	74010100	6	"CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 11:07	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 07:59	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 07:50	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 07:46	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 07:43	74010100	6	"CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 06:43	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 01:18	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 01:01	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/23/2025 00:13	74010100	6	"CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 23:52	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 23:50	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 23:45	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 23:33	74010100	6	"CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 22:40	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 20:32	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 20:14	74010100	6	"CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 19:39	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 11:15	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 2 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 10:58	74010100	6	"CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 10:48	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 10:23	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 2 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 10:08	74010100	6	"CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 2.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/22/2025 09:43	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/21/2025 23:16	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/21/2025 22:57	74010100	6	"CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/21/2025 22:07	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/21/2025 21:46	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/21/2025 21:26	74010100	6	"CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/21/2025 20:59	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/21/2025 17:52	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/21/2025 17:40	68010300	4	"DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/21/2025 17:38	74010100	6	"CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=a0:68:7e:ab:cf:2d;CMTS-MAC=00:90:f0:32:11:00;CM-QOS=1.1;CM-VER=3.1;"
11/21/2025 17:34	74010100

  • Same CMTS-MAC (00:90:f0:32:11:00)

  • Events on same dates

  • Both logs show :33 and :59 minute markers (overlapping)

  • Different modem manufacturers (proves it’s not equipment-specific)

  • Different log formats show the EXACT SAME PATTERN

Both modems are responding to the same R-PHY node crash/restart, just at different layers of the network stack. The ~30-minute lag is expected because upstream errors take time to cascade through the downstream systems.

My Attempts to Fix It

I called support. Multiple times. They blamed my WiFi (I’m hardwired). They blamed my modem (an Xfinity Approved MB8611). They blamed my router (I tested with multiple devices). They sent a subcontracted technician. Then another subcontracted technician. Then a subcontracted crew. The crew ran a new coax line and grounded it to a water pipe that turns into PVC when it enters the ground (this doesn’t ground anything). Then they sent an Xfinity technician to look at the line.

The problem never changed. The only thing that changed is my download speed dropped from advertised 1200Mbps to <500Mbps.

I escalated to retention. They offered me nothing. I provided detailed technical documentation showing the exact pattern of the outages, the minute markers they occur at, the exact duration every single time. They didn’t understand it. They couldn’t escalate it.

I was transferred to technical support. The person did not care and put me on speaker phone with so much background noise I couldn’t hear myself think. I imagine he was rolling his eyes while trying his utmost to care less.

My Neighbor’s Attempts to Fix It

He called Xfinity about his TV cutting out repeatedly. The technician told him his UPS grounding his coax cable was causing the problem. So he ungrounded the cable, pocketed the spare cable, and my neighbor kept having the same issues.

What I Found

Just in the last 72 hours I have documented 20 consecutive outages using OPNSense’s built in gateway uptime monitor. Here’s what they show:

Every single outage lasted 124.8 ± 1.3 seconds. That’s not random hardware failure. That’s a timeout value hardcoded into something in Xfinity’s infrastructure.

The outages cluster at specific minute markers. 35% start at minute :4days4. 35% start at minute :29. This is scheduled automation. This is likely a cron job or automated task running at those exact times every hour.

The outages peak at specific hours. Most happen between noon and 1 PM. Others cluster in early morning around 2-3 AM. This is not random.

This is an infrastructure problem on Xfinity’s network. Not on my end. Not on my neighbor’s end. Upstream. Somewhere on their equipment something is failing for exactly 125 seconds multiple times per day.

I have the data. I have the patterns. I have another customer (my neighbor) on a different line experiencing the exact same thing.

Xfinity has all this information. They know about the problem. They just won’t investigate it.

Why They Won’t Fix It

  1. Support can’t understand technical data. They follow scripts. When I attempted to explain monitoring logs they had no framework for discussing it. They blamed my equipment because that’s what they’re trained to do.
  2. Nobody has authority to escalate. Retention transferred me to tech support. Tech support couldn’t care nor help. They dug up my yard and placed a new line which did nothing to solve the problem. Nobody would actually order an investigation into the upstream infrastructure.
  3. There’s no pressure to fix it. Xfinity is the only gigabit provider in this area. No competition. No alternatives. I can’t leave. So they don’t have to care.
  4. A 2-minute outage every few hours is “tolerable.” It’s annoying enough to frustrate customers but not enough to make them quit (since they have nowhere else to go). It’s cheap to ignore compared to actually investigating and fixing it.

There’s Also a Security Problem

About half of the Xfinity junction boxes in my neighborhood are unlocked or broken. Anyone can walk up and disconnect whomever they want.

If your home security system is on Xfinity with no wireless backup, someone can just walk to the street and physically disconnect your internet, rob your house, and your security system won’t notify you.

I’m Out of Options

I’ve done everything I can do as a customer:

  • Documented the problem professionally
  • Escalated through all available channels
  • Provided technical evidence
  • Been ignored at every level

The problem is real. My neighbor confirms it. Everyone downstream of whatever is broken on their infrastructure probably has it too.

I can’t fix this. Only Xfinity can. And they won’t.

So I’m publishing this hoping someone with actual authority, perhaps someone at a regulatory agency, someone at a news outlet, someone who has power over Xfinity sees this and decides to actually investigate.

Because I’m out of options. My neighbors are out of options. And Xfinity’s counting on us staying out of options. Because this is the reality of my neighborhood (source):

If you’re in Sacramento County and have Xfinity internet, check two things:

1. Walk to your junction box. Is it locked? If not, you have a physical security problem.

2. Look at where your cable grounds. Does it go to your electrical panel? Or to a water pipe? If it’s a water pipe or PVC, that’s wrong.

3. Have you noticed your connection drop briefly multiple times a day? Same times of day? If you see a pattern, document it. You might have the same problem.

If you want to report this:

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Comments

  1. The author has correctly identified that the issue stems from an upstream infrastructure problem driven by an automated schedule (likely a cron job). However, both the author—and specifically the technicians—are missing a critical aspect of the diagnosis regarding the “125-second” duration.

    The Diagnosis: R-PHY Node Crash or Process Restart

    The problem is almost certainly a software/firmware crash on the local R-PHY Node (the “fiber to the curb” device that replaced the old analog nodes), triggered by a scheduled telemetry or maintenance task.

    What Is Being Missed

    The “125 Seconds” Is the Modem’s Re-Sync Time, Not a Network Timeout

    The author suggests that “125 seconds” is a timeout hardcoded into Xfinity’s infrastructure.
    It is more likely that the 125 seconds simply represents the time required for the cable modem to reboot and re-acquire a signal (Scan → Sync → Range → DHCP → Online).
    Key Point: The “cron job” (trigger) isn’t lasting 125 seconds; the trigger is likely instantaneous (due to a crash or a line reset). The modem detects the signal loss, drops connection, and initiates its boot sequence, consistently taking about 2 minutes. This reliability stems from the modem’s boot process, not a network timer.

    The Trigger: Automated “Proactive Network Maintenance” (PNM) or Telemetry

    The precision of outages (at :29 and :44) matches a network-synchronized clock (NTP).
    This pattern aligns with Proactive Network Maintenance (PNM) scans or a specific telemetry daemon running on the Node (likely an R-PHY device with Linux).
    Scenario: At :29 and :44, the Node initiates a diagnostic (such as upstream spectrum analysis or a mid-split band check). This triggers a bug (memory leak or conflict), crashing the upstream PHY module on the node. Although the module restarts instantly, all modems on the affected node lose sync and must reboot/re-range.

    What the Technicians Are Missing

    Scope: Technicians are currently troubleshooting physical layer (Layer 1) issues at the premises (e.g., grounding, connectors, signal levels), searching for noise (ingress) or attenuation.
    The Real Issue: The root cause is a logical layer (Layer 2/3) failure at the Node. Signal levels appear normal to the technician unless the Node crashes during their visit.
    The Fix: Technicians cannot solve this on-site. It requires escalating a ticket to the Maintenance/Headend Engineering team to inspect the Node’s system logs (not the modem’s logs) for “process crash,” “kernel panic,” or “module restart” events correlated with the :29/:44 timestamps.

    Summary of the “Missed” Diagnosis

    Author’s Miss: The “125s” is likely the modem’s own recovery time, not an ISP “timeout.”
    Technicians’ Miss: They are mistakenly treating a software/firmware failure on the Node as a physical cabling issue at the home. Resolution requires escalation to the OSP (Outside Plant) Maintenance team to investigate the Node’s software stability and cron logs.

    Reply

    • I don’t know about CA, but in general cable companies are licensed at the county level, those licenses are up for periodic renewal, and there is always a local commission who handles complaints about the cable company. Cable companies generally hate getting complaints from these guys. It’s not a perfect system, since oftentimes that.relationship is too cozy and insufficiently adversarial, but I would suggest leaning on your local commission hard to get them to resolve this. In your case, that commission is https://sacmetrocable.saccounty.gov/SMCTC/Pages/default.aspx.

      Also, using traceroute from your local computer while things are operational to identify which routers your traffic bounces on the way to the public Internet, and then running this again during the outage might give you insight into where the problem lies with Verizon. One possibility is that they have a router that is just resetting periodically — memory leak? — and it takes 125 seconds to restart.

      Personally, I think you should rule out your modem by renting a Comcast one for a month (if there is no minimum rental period) or ask them for a temporary loaner. If the problem goes away, that’s more data, and possibly another complaint to the commission, that Comcast has configured their network to prevent it working well with 3rd party modems (which of course we wouldn’t out past them).

      Reply

    • Please do NOT post output from an LLM like this again. You are adding nothing to the conversation and wasting screen real estate with this slop.

      Reply

    • If the author wanted to ask an LLM about their problem, they could do it themselves. Don’t post LLM slop without verifying the information yourself, you’re not helping.

      Reply

    • I had similar issues. They don’t have any one person who oversees things. Just a series of contractors targeted at specific jobs. Really bad way to run a company. File a complaint on the FCCs website and someone from their corporate office will call you.

      Reply

    • Cant find the top level comment button so replying here.
      I had a similar issue and it turned out to be the router software/firmware. Would get amazing speeds and then bam, it was like dialup. Putting the modem in bridge mode and using an external router solved it. Worth a try maybe.

      Reply

  3. Check your modem logs. They are usually accessible via a private IP address (try 192.168.100.1), look at the stickers on your modem for a diagnostics service page. This probably won’t fix the problem, but it will at least help gather more information.

    Reply

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