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Solved
CM1000 Xfinity issues
I am quite frustrated at this point. I had a CM600 modem to support Comcast's Extreme 150 service. I've had it for a few years and was consistently getting 160 to 170mbps speed from it. About thre...
Well it is finally fixed. The tech showed up today and I showed him the two frequencies that were having the problem. He checked outside, and then at the tap. He came into the house and said he needed to call a bucket truck in to fix it. I got a recorded call from Comcast that they were working to fix the issue. I got a second call an hour later that the issue was fixed. I ran a speed test and got a consistent 160mbps (yay!). I used the reset button on the modem and let it re-provision. All the signal/noise and power levels were good and there were no uncorrectable codewords. They didn't tell me what they fixed, but at long last, it is fixed.
Forgot to add the modem information:
| Hardware Version | 2.02 |
| Firmware Version | V3.01.02 |
| Cable Modem Serial Number | 4L0477W102A3E |
| CM certificate | Installed |
| CM MAC | b0:39:56:4b:b8:68 |
Part of the problem is your firmware
| V3.01.02 |
3.01.04 is supposed to correct the issues with the ODFM channel dropping and fallback to DOCSIS 3.0 channels. Should be out by now. Uplug your modem from the power. Toggle your power button. Wait for 60 Seconds. Power it back up Check your verision.
BigQuark So here's the latest update. Comcast came out to my house yesterday and their engineer also called Netgear. They replaced the CM1000 with a Comcast modem and it worked. Before they came, I had gone in to look at the modem stats and the logs and I noticed the firmware had been updated to V3.01.04. I am not sure when that happened, but in the last week my problems actually got worse. Sometime in the early evening or in the middle of the night, my speed would actually drop from 70mbps (should be 150) to 1mbps. The only way I could get back to the 70mbps was sending a reset signal to the modem through the Xfinity App. I at first tried to unplug the modem and wating 60 seconds, but even that didn't work. Comcast showed up at 8AM yesterday and I was up at 6AM. I did a speed test before they got there and it was back down to 1mbps so I sent another reset signal to the modem through the Xfinity app and that restored the modem to the 70mbps. Once they put their modem on, I am now getting 175mbps which is what I was getting with the original CM300 before this all started. They have waived the monthly modem fee and will waive it again until firmware comes out that fixes the problem. V3.01.04 does not seem to be the version that fixes it. If there are logs I can get off the modem, let me know how and I will send them to you. I figure if I power it on and connect it to the ethernet port directly, I should be able to log in at 192.168.100.1. Thanks for keeping me up to date and let me know what you need. Many thanks
Warm regards,
Joe Noonan
Hi, Can you post your Basic modem signal page and also under the Avanced Tab can youpost the Event Log page? Thanks!
BigQuark Here is what I have for now. I would need to reconnect the modem and reprovision it and then put the comcast one back on and then reprovision that. First, here is confirmation of the version:
Firmware Version V3.01.04Here is the log. I will connect the modem later tonight when no one will be using the Internet.
Time Priority Description Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;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=b0:39:56:4b:b8:68;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; 2017-12-20, 09:37:38 Critical (3) Resetting the cable modem due to docsDevResetNow Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;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=b0:39:56:4b:b8:68;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;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=b0:39:56:4b:b8:68;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; 2017-12-20, 01:01:48 Critical (3) Resetting the cable modem due to docsDevResetNow Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;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=b0:39:56:4b:b8:68;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; 2017-12-18, 08:02:22 Critical (3) Resetting the cable modem due to docsDevResetNow Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;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=b0:39:56:4b:b8:68;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; 2017-12-16, 21:20:12 Critical (3) Resetting the cable modem due to docsDevResetNow Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;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=b0:39:56:4b:b8:68;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; 2017-12-16, 00:36:45 Critical (3) Resetting the cable modem due to docsDevResetNow 2017-12-15, 12:34:12 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;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=b0:39:56:4b:b8:68;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 08:06:20 Critical (3) Resetting the cable modem due to docsDevResetNow Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 07:38:29 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 07:34:45 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 07:33:21 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 07:32:44 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 07:32:38 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 07:32:34 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 06:31:18 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 06:31:12 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 06:30:17 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 06:30:15 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 06:30:10 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 06:30:09 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 06:27:34 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 06:27:30 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 05:28:12 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:01:5c:a7:12:4e;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 05:22:21 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; 2017-12-15, 05:22:20 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:4b:b8:68;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;