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Forum Discussion
CM1200 loses connection after 24 hours
Just bought this a week ago, and after troubleshooting my router, having Comcast come to the home to check the entire line (they replaced the connection at the pole and made sure there were no unnecessary splitters), I’ve concluded this new modem is the problem.
My connection is great after I reset the modem, I get 170M down and 25M up. After various amounts of time though, usually 18-36 hours, the speeds drop, and I also randomly lose connection for a second or two and then reconnect (I can monitor this as I have a Netgear 6200 usb WiFi adapter, and it displays a popup message every time you connect to WiFi). After a power cycle of the modem, things go back to normal. Below are my recent logs. I’ve opened a case, and I sounds like after talking to a rep last night I may have a faulty modem? They said to see if it keeps acting up and call them back tomorrow, which I will do.
I haven’t taken the time to search the forums for others with the same issue, but more or less wanted to share my experience so far with the CM1200. Perhaps this is a well known issue others are experiencing.
Time Priority Description
Wed Feb 12 17:25:08 2020 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Wed Feb 12 17:25:03 2020 Notice (6) TLV-11 - unrecognized OID;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;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=28:80:88:af:7e:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 21:16:37 2020 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:05:05 2020 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:05:04 2020 Notice (6) TLV-11 - unrecognized OID;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:04:55 2020 Notice (6) Honoring MDD; IP provisioning mode = IPv6
Mon Feb 10 18:04:44 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:04:08 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:04:08 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:03:46 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:03:45 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:03:02 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:03:02 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:02:41 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:02:41 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:00:45 2020 Warning (5) MDD message timeout;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:00:44 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:00:39 2020 Warning (5) MDD message timeout;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:00:38 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:41:04 2020 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:40:59 2020 Notice (6) TLV-11 - unrecognized OID;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:35:47 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:35:47 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:35:26 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:35:26 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:35:26 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:35:26 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:34:10 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:34:10 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:32:10 2020 Warning (5) MDD message timeout;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:32:10 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:32:04 2020 Warning (5) MDD message timeout;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:32:03 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:19:49 2020 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:19:44 2020 Notice (6) TLV-11 - unrecognized OID;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
My connection is great after I reset the modem, I get 170M down and 25M up. After various amounts of time though, usually 18-36 hours, the speeds drop, and I also randomly lose connection for a second or two and then reconnect (I can monitor this as I have a Netgear 6200 usb WiFi adapter, and it displays a popup message every time you connect to WiFi). After a power cycle of the modem, things go back to normal. Below are my recent logs. I’ve opened a case, and I sounds like after talking to a rep last night I may have a faulty modem? They said to see if it keeps acting up and call them back tomorrow, which I will do.
I haven’t taken the time to search the forums for others with the same issue, but more or less wanted to share my experience so far with the CM1200. Perhaps this is a well known issue others are experiencing.
Time Priority Description
Wed Feb 12 17:25:08 2020 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Wed Feb 12 17:25:03 2020 Notice (6) TLV-11 - unrecognized OID;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;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=28:80:88:af:7e:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 21:16:37 2020 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:05:05 2020 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:05:04 2020 Notice (6) TLV-11 - unrecognized OID;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:04:55 2020 Notice (6) Honoring MDD; IP provisioning mode = IPv6
Mon Feb 10 18:04:44 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:04:08 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:04:08 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:03:46 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:03:45 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:03:02 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:03:02 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:02:41 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:02:41 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:00:45 2020 Warning (5) MDD message timeout;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:00:44 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:00:39 2020 Warning (5) MDD message timeout;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 18:00:38 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:41:04 2020 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:40:59 2020 Notice (6) TLV-11 - unrecognized OID;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:35:47 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:35:47 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:35:26 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:35:26 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:35:26 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:35:26 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:34:10 2020 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:34:10 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:32:10 2020 Warning (5) MDD message timeout;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:32:10 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:32:04 2020 Warning (5) MDD message timeout;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:32:03 2020 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:19:49 2020 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
Mon Feb 10 17:19:44 2020 Notice (6) TLV-11 - unrecognized OID;CM-MAC=28:80:88:af:7e:00;CMTS-MAC=00:01:5c:ae:ee:67;CM-QOS=1.1;CM-VER=3.1;
1 Reply
Are you using link aggregation? the CM1200 is known to have some issues with link aggregation as well as some routers have been known to have issues with it.
what router are you using?
If you log into the cm1200, take a screen snip of the modem's connection page. comcast techs aren't the best and the link connection page gives us a snap shot of your connection back to the isp.
also, if you have any amplifiers, attenuators, splitters in line, remove them.
I usually recommend people attach the modem directly to where the coax enters the home. This prevents issues with the wiring in the home to be causing problems. If this isn't possible, check you line for kinks, damanged cable, worn cable, cheap connectors, corrosion. Sometimes simply taking a connector off and putting it back on cleans it up enough.
