Community Forum

T-3 Timeout issues and high upstream packet loss

Highlighted
Frequent Visitor

T-3 Timeout issues and high upstream packet loss

For months now, I've been trying to get connectivity issues resolved with Comcast support, with no resolution in sight. My modem logs are just filled with errors like these:

 

"Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:c0:3e:06:65:89;CMTS-MAC=00:cc:fc:61:33:21;CM-QOS=1.1;CM-VER=3.1;"

 

"RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=14:c0:3e:06:65:89;CMTS-MAC=00:cc:fc:61:33:21;CM-QOS=1.1;CM-VER=3.1;"

 

"Dynamic Range Window violation"

 

I frequently get long periods of 20% or more packet loss on the upload that basically makes it impossible to carry on a VoIP conversation or conference call, which is basically most of what I do for my job.

 

Pingplot images for reference:

https://imgur.com/a/tt9LfS2

 

Any help would be greatly appreciated because I feel like I've exhausted every endeavor I've tried, from phone calls, daily/nightly chats, multiple outage resolutions and maintenances in my area, and even a tech visit, where he confirmed everything from my house to the street looked good.

 

Any help would be appreciated.

 

Highlighted
Frequent Visitor

Re: T-3 Timeout issues and high upstream packet loss

My modem status:

 

Downstream Bonded Channels
Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
29 Locked QAM256 633000000 Hz -1.3 dBmV 40.7 dB 0 0
5 Locked QAM256 483000000 Hz -1.8 dBmV 40.6 dB 0 0
6 Locked QAM256 489000000 Hz -1.7 dBmV 40.7 dB 0 0
7 Locked QAM256 495000000 Hz -1.1 dBmV 40.8 dB 0 0
8 Locked QAM256 507000000 Hz -0.7 dBmV 40.8 dB 0 0
9 Locked QAM256 513000000 Hz -0.5 dBmV 40.9 dB 0 0
10 Locked QAM256 519000000 Hz -0.7 dBmV 40.8 dB 0 0
11 Locked QAM256 525000000 Hz -0.9 dBmV 40.8 dB 0 0
12 Locked QAM256 531000000 Hz -1.1 dBmV 40.8 dB 0 0
13 Locked QAM256 537000000 Hz -1.5 dBmV 40.7 dB 0 0
14 Locked QAM256 543000000 Hz -1.6 dBmV 40.8 dB 0 0
15 Locked QAM256 549000000 Hz -1.3 dBmV 40.8 dB 0 0
16 Locked QAM256 555000000 Hz -1.3 dBmV 40.8 dB 0 0
17 Locked QAM256 561000000 Hz -1.2 dBmV 40.7 dB 0 0
18 Locked QAM256 567000000 Hz -1.0 dBmV 40.9 dB 0 0
19 Locked QAM256 573000000 Hz -1.3 dBmV 40.8 dB 0 0
20 Locked QAM256 579000000 Hz -1.2 dBmV 40.9 dB 0 0
21 Locked QAM256 585000000 Hz -1.2 dBmV 40.8 dB 0 0
22 Locked QAM256 591000000 Hz -1.3 dBmV 40.9 dB 0 0
23 Locked QAM256 597000000 Hz -0.9 dBmV 40.9 dB 0 0
24 Locked QAM256 603000000 Hz -0.6 dBmV 41.0 dB 0 0
25 Locked QAM256 609000000 Hz -0.8 dBmV 40.9 dB 0 0
26 Locked QAM256 615000000 Hz -0.8 dBmV 40.8 dB 0 0
27 Locked QAM256 621000000 Hz -1.2 dBmV 40.8 dB 0 0
28 Locked QAM256 627000000 Hz -1.4 dBmV 40.7 dB 0 0
30 Locked QAM256 639000000 Hz -2.4 dBmV 40.1 dB 0 0
31 Locked QAM256 645000000 Hz -1.6 dBmV 40.5 dB 0 0
32 Locked QAM256 651000000 Hz -1.2 dBmV 40.5 dB 0 0
33 Locked QAM256 657000000 Hz -1.2 dBmV 40.6 dB 0 0
34 Locked QAM256 663000000 Hz -0.9 dBmV 40.5 dB 0 0
35 Locked QAM256 669000000 Hz -1.3 dBmV 40.4 dB 0 0
36 Locked QAM256 675000000 Hz -1.2 dBmV 40.3 dB 0 0
159 Locked Other 690000000 Hz 0.6 dBmV 39.8 dB 990 0


 

 
Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 4 Locked SC-QAM Upstream 35700000 Hz 6400000 Hz 41.0 dBmV
2 1 Locked SC-QAM Upstream 16200000 Hz 6400000 Hz 40.0 dBmV
3 2 Locked SC-QAM Upstream 22700000 Hz 6400000 Hz 41.0 dBmV
4 3 Locked SC-QAM Upstream 29200000 Hz 6400000 Hz 41.0 dBmV
Highlighted
Frequent Visitor

Re: T-3 Timeout issues and high upstream packet loss

Bump.

 

I've gone through all the troubleshooting recommendations on the forum, including even purchasing an entirely new cable modem and router instead of the Xfinity-provided one, replacing coax and ethernet cables, the wall socket, and lone splitter outside my house.

 

Issue still happens constantly, and only really manifests itself on my upload. I finally got support to send me a tech this Friday, so we'll see if they are more helpful than the last one. Will reply here with results.

Highlighted
Expert

Re: T-3 Timeout issues and high upstream packet loss

FWIW, the signal stat numbers are well within spec. Good luck with the tech visit !



I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!