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T3 T4 timeout issues with gig / SB8200 dropping internet

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T3 T4 timeout issues with gig / SB8200 dropping internet

Our internet has been dropping at random for a long time (probibly close to a year) due to the modem resetting. I have called comcast phone support multiple times (They are next to useless trying to troubleshoot wifi issues when its clearly the modem resetting) who had a tech come out last time and check levels. Everything is fine when they are here but at random times throughout the day and night the modem gets these t3 t4 errors and resets. 

 

I pay for the top tier gig service with unlimited / no data caps and it hurts a lot to keep paying them that much money every month for something that is not reliable. If we had fiber here I would do it to get off of the shared coax.

 

Does anyone know who at comcast I can talk to that will not just tell me to reboot my modem or blame my customer owned modem for the problem? BTW I have talked to arris who looked at the logs and told me to contact comcast and show them the T3 T4 errors.

 

Here are the current signals and logs

 

 

Procedure Status Comment
Acquire Downstream Channel 513000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Configuration File OK  
Security Enabled BPI+
DOCSIS Network Access Enabled Allowed  

 
Downstream Bonded Channels
Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
17 Locked QAM256 513000000 Hz 3.9 dBmV 39.2 dB 0 0
12 Locked QAM256 477000000 Hz 3.3 dBmV 38.8 dB 0 0
13 Locked QAM256 483000000 Hz 3.3 dBmV 38.9 dB 0 0
14 Locked QAM256 489000000 Hz 3.7 dBmV 39.0 dB 0 0
15 Locked QAM256 495000000 Hz 3.9 dBmV 38.9 dB 0 0
16 Locked QAM256 507000000 Hz 3.8 dBmV 39.2 dB 0 0
18 Locked QAM256 519000000 Hz 4.1 dBmV 39.3 dB 0 0
19 Locked QAM256 525000000 Hz 3.7 dBmV 39.2 dB 0 0
20 Locked QAM256 531000000 Hz 3.8 dBmV 39.3 dB 0 0
21 Locked QAM256 537000000 Hz 4.0 dBmV 39.4 dB 0 0
22 Locked QAM256 543000000 Hz 3.9 dBmV 39.3 dB 0 0
23 Locked QAM256 549000000 Hz 4.1 dBmV 39.3 dB 0 0
24 Locked QAM256 555000000 Hz 4.0 dBmV 39.4 dB 0 0
25 Locked QAM256 561000000 Hz 3.6 dBmV 39.3 dB 0 0
26 Locked QAM256 567000000 Hz 3.2 dBmV 39.0 dB 0 0
27 Locked QAM256 573000000 Hz 2.7 dBmV 38.8 dB 0 0
28 Locked QAM256 579000000 Hz 2.1 dBmV 38.7 dB 0 0
29 Locked QAM256 585000000 Hz 1.7 dBmV 38.5 dB 0 0
30 Locked QAM256 591000000 Hz 2.3 dBmV 38.8 dB 0 0
31 Locked QAM256 597000000 Hz 2.9 dBmV 38.9 dB 0 0
32 Locked QAM256 603000000 Hz 3.1 dBmV 39.1 dB 0 0
33 Locked QAM256 609000000 Hz 2.9 dBmV 39.0 dB 0 0
34 Locked QAM256 615000000 Hz 3.2 dBmV 38.9 dB 0 0
35 Locked QAM256 621000000 Hz 4.3 dBmV 39.2 dB 0 0
36 Locked QAM256 627000000 Hz 4.8 dBmV 39.4 dB 0 0
37 Locked QAM256 633000000 Hz 5.1 dBmV 39.5 dB 0 0
38 Locked QAM256 639000000 Hz 5.0 dBmV 39.4 dB 0 0
39 Locked QAM256 645000000 Hz 4.9 dBmV 39.5 dB 0 0
40 Locked QAM256 651000000 Hz 4.6 dBmV 39.3 dB 0 0
41 Locked QAM256 657000000 Hz 4.5 dBmV 39.4 dB 0 0
42 Locked QAM256 663000000 Hz 4.1 dBmV 39.0 dB 0 0
48 Locked Other 805000000 Hz 0.6 dBmV 35.2 dB 167674706 0



 
Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 86 Locked SC-QAM Upstream 30100000 Hz 6400000 Hz 44.0 dBmV
2 85 Locked SC-QAM Upstream 36500000 Hz 6400000 Hz 44.0 dBmV
3 87 Locked SC-QAM Upstream 23700000 Hz 6400000 Hz 43.0 dBmV
4 88 Locked SC-QAM Upstream 17300000 Hz 6400000 Hz 43.0 dBmV



 

Current System Time: Fri Aug 2 23:08:23 2019

 

 

 

 

 

 

Event Log
The table below contains the log of events that the SB8200 has detected. This log can be important to the service provider to help diagnose and correct problems, if any should occur.

Date Time Event ID Event Level Description
08/02/2019 22:38 67061600 6 "DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 2436694066 6 "Honoring MDD; IP provisioning mode = IPv6"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
07/19/2019 09:40 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
07/19/2019 09:39 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
07/19/2019 09:39 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
07/19/2019 09:39 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
07/19/2019 09:39 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
07/19/2019 09:39 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
07/19/2019 09:38 82000400 3 "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"
07/19/2019 09:38 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=8c:61:a3:c3:c1:fd;CMTS-MAC=00:01:5c:6e:9e:5b;CM-QOS=1.1;CM-VER=3.1;"

 

 

 

Expert

Re: T3 T4 timeout issues with gig / SB8200 dropping internet

Yep. The stats are good. The error logs, not so much. If this is with a WiFi connection, for a test, does a computer hardwired directly to the 8200 (no router or WiFi in the mix) have the same problem ? Do you actually see the state of the modem lights change (do they blink) when this occurs ?



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