I've tried everything on my end repeatedly for weeks to resolve this issue, which seems to only be compounded by dense tier 1 support.
There are no splitters. Physical PC connection to the modem to the wall cable. Constant disconnections as though im being throttled or unplugged.
Fri Jun 26 14:54:04 2020 | Notice (6) | TLV-11 - unrecognized OID;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Time Not Established | Notice (6) | Honoring MDD; IP provisioning mode = IPv6 |
Time Not Established | Critical (3) | No Ranging Response received - T3 time-out |
Time Not Established | Notice (6) | WiFi Interface [wl0] set to Channel 36 (Side-Band Channel:N/A) - Reason:INIT |
Fri Jun 26 14:52:41 2020 | Critical (3) | Resetting the cable modem due to docsDevResetNow |
Thu Jun 25 07:16:03 2020 | Critical (3) | SYNC Timing Synchronization failure - Failed to receive MAC SYNC frame within time-out period;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Thu Jun 25 07:15:06 2020 | Critical (3) | SYNC Timing Synchronization failure - Failed to receive MAC SYNC frame within time-out period;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Thu Jun 25 07:13:43 2020 | Critical (3) | Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Thu Jun 25 07:11:08 2020 | Critical (3) | SYNC Timing Synchronization failure - Failed to receive MAC SYNC frame within time-out period;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Thu Jun 25 07:08:13 2020 | Critical (3) | Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Thu Jun 25 06:33:32 2020 | Critical (3) | Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Thu Jun 25 06:33:28 2020 | Critical (3) | SYNC Timing Synchronization failure - Failed to receive MAC SYNC frame within time-out period;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Thu Jun 25 06:33:10 2020 | Critical (3) | SYNC Timing Synchronization failure - Failed to receive MAC SYNC frame within time-out period;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Thu Jun 25 06:32:34 2020 | Critical (3) | Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Thu Jun 25 06:32:07 2020 | Critical (3) | SYNC Timing Synchronization failure - Failed to receive MAC SYNC frame within time-out period;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Thu Jun 25 06:31:15 2020 | Critical (3) | SYNC Timing Synchronization failure - Failed to receive MAC SYNC frame within time-out period;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Tue Jun 23 10:41:24 2020 | Critical (3) | Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Tue Jun 23 10:41:13 2020 | Critical (3) | SYNC Timing Synchronization failure - Failed to receive MAC SYNC frame within time-out period;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Tue Jun 23 10:41:02 2020 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Time Not Established | Critical (3) | No Ranging Response received - T3 time-out |
Time Not Established | Critical (3) | No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | No Ranging Response received - T3 time-out |
Time Not Established | Critical (3) | No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | No Ranging Response received - T3 time-out |
Time Not Established | Critical (3) | No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | No Ranging Response received - T3 time-out |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | No Ranging Response received - T3 time-out |
Time Not Established | Critical (3) | No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | No Ranging Response received - T3 time-out |
Time Not Established | Critical (3) | No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | No Ranging Response received - T3 time-out |
Time Not Established | Critical (3) | No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | No Ranging Response received - T3 time-out |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Please also post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.
What is the exact make and model number of the modem ?
Downstream Bonded Channels | ||||||||
---|---|---|---|---|---|---|---|---|
Channel | Lock Status | Modulation | Channel ID | Frequency | Power | SNR | Corrected | Uncorrectables |
1 | Locked | QAM256 | 8 | 429000000 Hz | -1.5 dBmV | 39.8 dB | 105 | 43 |
2 | Locked | QAM256 | 9 | 435000000 Hz | -1.4 dBmV | 39.9 dB | 0 | 0 |
3 | Locked | QAM256 | 10 | 441000000 Hz | -1.4 dBmV | 39.0 dB | 0 | 0 |
4 | Locked | QAM256 | 11 | 453000000 Hz | -1.1 dBmV | 39.5 dB | 0 | 0 |
5 | Locked | QAM256 | 12 | 459000000 Hz | -1.1 dBmV | 39.9 dB | 0 | 0 |
6 | Locked | QAM256 | 13 | 465000000 Hz | -0.8 dBmV | 40.3 dB | 102 | 25 |
7 | Locked | QAM256 | 14 | 471000000 Hz | -0.7 dBmV | 40.1 dB | 0 | 0 |
8 | Locked | QAM256 | 15 | 477000000 Hz | -0.6 dBmV | 40.2 dB | 0 | 0 |
Upstream Bonded Channels | ||||||
---|---|---|---|---|---|---|
Channel | Lock Status | US Channel Type | Channel ID | Symbol Rate | Frequency | Power |
1 | Locked | ATDMA | 27 | 5120 Ksym/sec | 23700000 Hz | 44.0 dBmV |
2 | Locked | ATDMA | 25 | 5120 Ksym/sec | 36500000 Hz | 45.0 dBmV |
3 | Locked | ATDMA | 26 | 5120 Ksym/sec | 30100000 Hz | 44.5 dBmV |
4 | Locked | ATDMA | 28 | 5120 Ksym/sec | 17300000 Hz | 43.0 dBmV |
The Xfinity Tech was out here today. My DownStream SNR was down to 32 (again, thanks Xfinity's customer service reps that kept telling me nothing was wrong for the last 3-6 weeks). There was apparently some water damage to the lines in the box on the house, a new ground needed, and the local box had something replaced too.
As you can see, the SNR is hitting the ideal 40 now, however despite this, I am still getting disconnects (5'ish since the Comcast Xfinity Rep left 2 hours ago).
The new event log shows a full page (which caps at 60 I think) of SYNC Timing failures, below.
Sun Jun 28 08:43:41 2020 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Sun Jun 28 08:43:11 2020 | Warning (5) | MDD message timeout;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Sun Jun 28 08:43:10 2020 | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
Sun Jun 28 08:40:52 2020 | Notice (6) | TLV-11 - unrecognized OID;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:01:5c:65:38:64;CM-QOS=1.1;CM-VER=3.0; |
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=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
Time Not Established | Critical (3) | SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=30:60:23:74:a9:b8;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
C:\WINDOWS\system32>ping -t -l 900 bbc.co.uk
Pinging bbc.co.uk [2a04:4e42:600::81] with 900 bytes of data:
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=11ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=9ms
Reply from 2a04:4e42:600::81: time=11ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=12ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=11ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=11ms
Reply from 2a04:4e42:600::81: time=13ms
Reply from 2a04:4e42:600::81: time=11ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=10ms
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Reply from 2a04:4e42:600::81: time=21ms
Reply from 2a04:4e42:600::81: time=14ms
Reply from 2a04:4e42:600::81: time=11ms
Reply from 2a04:4e42:600::81: time=11ms
Reply from 2a04:4e42:600::81: time=12ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=11ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=12ms
Reply from 2a04:4e42:600::81: time=10ms
Reply from 2a04:4e42:600::81: time=12ms
Reply from 2a04:4e42:600::81: time=11ms
Reply from 2a04:4e42:600::81: time=11ms
Reply from 2a04:4e42:600::81: time=12ms
Reply from 2a04:4e42:600::81: time=11ms
Reply from 2a04:4e42:600::81: time=11ms
Reply from 2a04:4e42:600::81: time=12ms
Reply from 2a04:4e42:600::81: time=11ms
Request timed out.
Request timed out.
Request timed out.
Request timed out.
A visual representation of my internet by ping... constant on/off. Net good, Net bad (those 900bytes were more often timed out then successful).
900 bytes. That's a lot of network stress ! What do the standard 32-byte ping probes look like ?
The 900 bytes SHOULD be irrelevant in this context, the take away should be that the ping succeeds for several seconds, the loses connection/response for several minutes, then regains connection, then loses it.
My 100+ Mbps down rate and 5mbps up rate (Xfinity Performance Select, internet only) should NOT care enough about 0.9 kilobytes rate to warrant complete disconnects or prompt intermitent connectivity.
https://xfinityorg.speedtestcustom.com/result/be708280-b978-11ea-a46e-e1f1aa3cc433
That being said, the 32byte test was the same, with slightly more successful replies before timing out again for periods of time.
No. It's not irrelevant. Quite the contrary. ICMP packet based probes are already de-prioritized / rate limited by network routers and servers in the first place. If you bombard then even more, then even more will not be returned.
This is not to say that you are not having some kind of connectivity problem. Start here;
https://forums.xfinity.com/t5/Your-Home-Network/Internet-Troubleshooting-Tips/m-p/3310447#M316652