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How a monopoly ISP refuses to fix upstream infrastructure – The Sacramento Bear

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A documented case of infrastructure failure, failed growth and a company’s refusal to investigate.

The situation is: I have outages. My neighbor also has a similar cut. Xfinity won’t fix it.

I purchased Xfinity Internet in June 2024. Immediately, my connection started dropping. Several times a day. Every day. After troubleshooting every appliance I had and questioning my sanity my neighbor complained about the same thing which made me realize it wasn’t my appliance.

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

There were approximately 3,387 outage incidents in the 17 months of my service period, totaling 117+ hours of cumulative downtime.

This outage pattern has been repeated thousands of times. It is consistent, predictable and it follows an automatic schedule.

My neighbor also has the same problem. detached house. Separate line from a separate junction box. The same 125-second interruption is happening at the same time of the 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 "
DOCSIS event log from MODEM (MAC unclear)

00:00:36

Fri Nov 21 2025 Critical (3) UCD invalid or channel unusable;CM-MAC=00:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

time not established

Critical (3) Sync Time Synchronization Failure – Failed to obtain QAM/QPSK symbol time;;CM-MAC=00:XX:XX:XX:XX: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:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

07:00:37

Fri Nov 21 2025 Critical (3) UCD invalid or channel unusable;CM-MAC=00:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

time not established

Critical (3) Sync Time Synchronization Failure – Failed to obtain QAM/QPSK symbol time;;CM-MAC=00:XX:XX:XX:XX: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:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

14:48:44

Fri Nov 21 2025 Critical (3) UCD invalid or channel unusable;CM-MAC=00:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

time not established

Critical (3) Sync Time Synchronization Failure – Failed to obtain QAM/QPSK symbol time;;CM-MAC=00:XX:XX:XX:XX: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:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

15:30:40

Fri Nov 21 2025 Critical (3) UCD invalid or channel unusable;CM-MAC=00:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

time not established

Critical (3) Sync Time Synchronization Failure – Failed to obtain QAM/QPSK symbol time;;CM-MAC=00:XX:XX:XX:XX: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:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

03:00:36

Saturday 22 November 2025 Critical (3) UCD Invalid or channel unusable;CM-MAC=00:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

time not established

Critical (3) Sync Time Synchronization Failure – Failed to obtain QAM/QPSK symbol time;;CM-MAC=00:XX:XX:XX:XX: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:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

04:00:39

Saturday 22 November 2025 Critical (3) UCD Invalid or channel unusable;CM-MAC=00:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

time not established

Critical (3) Sync Time Synchronization Failure – Failed to obtain QAM/QPSK symbol time;;CM-MAC=00:XX:XX:XX:XX: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:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

11:00:30

Saturday 22 November 2025 Critical (3) UCD Invalid or channel unusable;CM-MAC=00:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

11:00:30

Saturday 22 November 2025 Critical (3) Unicast Maintenance Ranging started – No response received – T3 time-out;CM-MAC=00:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

11:00:35

Saturday 22 November 2025 Critical (3) UCD Invalid or channel unusable;CM-MAC=00:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

time not established

Critical (3) Sync Time Synchronization Failure – Failed to obtain QAM/QPSK symbol time;;CM-MAC=00:XX:XX:XX:XX: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:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

11:45:35

Saturday 22 November 2025 Critical (3) UCD Invalid or channel unusable;CM-MAC=00:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

time not established

Critical (3) Sync Time Synchronization Failure – Failed to obtain QAM/QPSK symbol time;;CM-MAC=00:XX:XX:XX:XX: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:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

13:15:31

Saturday 22 November 2025 Critical (3) UCD Invalid or channel unusable;CM-MAC=00:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

time not established

Critical (3) Sync Time Synchronization Failure – Failed to obtain QAM/QPSK symbol time;;CM-MAC=00:XX:XX:XX:XX: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:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

time not established

Information (6) respect for MDD; IP provisioning mode = IPv6

18:15:32

Saturday 22 November 2025 Notice (6) DS Profile Assignment Changes. DS CHAN ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=00:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

18:15:39

Saturday 22 November 2025 Critical (3) UCD Invalid or channel unusable;CM-MAC=00:XX:XX:XX:XX:ac;CMTS-MAC=00:XX:XX:XX:XX:XX:00;CM-QOS=1.1;CM-VER=3.1;

my attempts to fix it

I called support. Many times. They blamed my wifi (I’m hardwired). They blamed my modem (an Xfinity approved MB8611 which worked flawlessly on Wave Broadband and Spectrum). They blamed my router (I tested with multiple devices). They sent a subcontracted technician. Then another subcontractor technician. Then a sub-contracted crew. The crew ran a new coax line and connected it to a water pipe which turns to PVC as it enters the ground (this doesn’t ground anything). They then sent an Xfinity technician to look at the line.

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

I proceeded to retention. They didn’t give me anything. I have provided detailed technical documentation showing the exact pattern of outages, at what minutes they occur, the exact duration each time. They did not understand this. They could not take it forward.

I was transferred to technical support. The person didn’t care and put me on speaker phone with so much background noise that I couldn’t even hear myself. I think he was rolling his eyes, trying his best to care less.

My Neighbor’s Attempt to Fix It

He called Xfinity about his TV repeatedly disconnecting. The technician told him that the problem was arising from grounding of the coax cable of his UPS. So he ungrounded the cable, put the extra cable in his pocket and my neighbor continued to have the same problems.

what did i get

Over the past 72 hours I have documented 20 consecutive outages using OpenSense’s built-in gateway uptime monitor. Here’s what they show:

Each outage lasted 124.8 ± 1.3 seconds. This is not random hardware failure. This is a timeout value that is hardcoded into something in Xfinity’s infrastructure.

Outages cluster at specific minute markers. 35% minutes start at :44. 35% minutes start at :29. This is scheduled automation. This is probably a cron job or automated task that is running at the exact same time every hour.

Reductions peak at specific hours. Mostly happens between noon and 1 pm. Others gather early in the morning around 2-3 am. This is not accidental.

This is an infrastructure problem on Xfinity’s network. Not from my side. Not from my neighbor. Upstream. Somewhere on their equipment something is failing several times a day for exactly 125 seconds.

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

Xfinity has all this information. They are aware of the problem. They won’t even investigate it.

why won’t they fix it

  1. Support cannot understand technical data. They follow the script. When I tried to explain the monitoring logs they had no framework to discuss this. They blamed my equipment because that’s what they’ve been trained to do.
  2. No one has the right to move forward. Retention got me transferred to technical support. Tech support couldn’t care or help. They dug up my yard and laid a new line which did not solve the problem. No one will actually order an investigation of the upstream infrastructure.
  3. There’s no pressure to get it right. Xfinity is the only gigabit provider in the area. no competition. No option. I can’t go. So they don’t need to care.
  4. A 2 minute reduction every few hours is “tolerable”. It’s annoying enough to frustrate customers but not enough to force them to quit (because they have nowhere else to go). It’s cheaper to ignore it than to actually investigate and fix it.

There is also a security problem

About half the Xfinity junction boxes in my neighborhood are open or broken. Anybody can come and cut whoever they want.

If your home security system is on

I’m out of options

I have done everything I can do as a customer:

  • Problem documented professionally
  • Pursued through all available channels
  • provide technical evidence
  • Ignored at every level

The problem is real. My neighbor has confirmed this. At the bottom of whatever is broken on their infrastructure, everyone probably has it too.

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

So I’m publishing this in the hopes that someone with real authority, maybe someone from a regulatory agency, someone from a news outlet, someone with authority on Xfinity will see this and decide to actually investigate.

Because I don’t have options. My neighbors have no choice. And Xfinity is counting on us being 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 close? If not, you have a physical security problem.

2. See where your cable is grounded. Does it go to your electrical panel? Or for water pipes? If it’s water pipe or PVC, it’s wrong.

3. Have you noticed that your connection stops for a while several times a day? Same time of day? If you notice a pattern, document it. You may also have the same problem.

If you want to report it:

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