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Need help with SB8200, Docsis and possible cmts glitch

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Re: Need help with SB8200, Docsis and possible cmts glitch

Well, Comcast is already aware of it but they can’t do anything about it because they have to wait for the fix to come from Arris, manufacturer of CMTS with the glitch, before they are able to deploy it. I’m not sure if there is a applicable workaround other than just using a D3.0 modem/gateway. I believe if the OFDM is not set as primary carrier where the D3.0 is primary carrier, however I’m not sure if that is a possible workaround or not and that is up to Comcast to determine if D3.0 carrier or OFDM carrier is the primary
Regular Visitor

Re: Need help with SB8200, Docsis and possible cmts glitch

Has anyone ever got a reply here stating Comcast is aware of this and working on it? I know of some second hand private messages to netcool but I haven’t been able to find much else.

Re: Need help with SB8200, Docsis and possible cmts glitch

You could try calling Comcast and ask if they can figure it out but I personally was able to talk with netcool on and just provide your CM-MAC address.
New Poster

Re: Need help with SB8200, Docsis and possible cmts glitch

I am having nearly the same issue, although I'm in the Chicago area

Regular Visitor

Re: Need help with SB8200, Docsis and possible cmts glitch

Thanks for the reply,
How can I find the Cmts on the SB8200 if it’s not in the event log. Has there been any timeframe posted for the cmts update?

Re: Need help with SB8200, Docsis and possible cmts glitch

Ok. Based on the description provided and if you are able to put your actual CMTS-MAC address into a MAC lookup tool, it does seem like you have the CMTS that has the OFDM carrier glitch. Currently as far as I’m aware of, the only way to get back to 200+ downloads would be to go back to a DOCSIS 3.0 modem until the CMTS is updated.
Regular Visitor

Need help with SB8200, Docsis and possible cmts glitch


I live in the Pittsburgh Pa area and recently purchased the SB8200. The 2nd light on the modem is blue and I don't have an old 3.0 modem to compare to. I have the blast package at 200/10 but I consistently test around 170/11(direct link, Win 10). Obviously I would love to get 200 or more and any tips would be appreciated. Ive looked at the modem logs but the only thing regarding cmts is ;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"  so I don't know how to see if I'm being affected by the head end glitch. Ive included the modem status page if that helps. I'm also not sure what to make of the corrected field, especially the 7.9 million number.


Sincerely, Sam



Procedure Status Comment
Acquire Downstream Channel 627000000 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
21 Locked QAM256 627000000 Hz 7.4 dBmV 38.1 dB 25 0
1 Locked QAM256 507000000 Hz 9.0 dBmV 39.4 dB 0 0
2 Locked QAM256 513000000 Hz 9.4 dBmV 39.4 dB 0 0
3 Locked QAM256 519000000 Hz 9.8 dBmV 39.5 dB 0 0
4 Locked QAM256 525000000 Hz 9.9 dBmV 39.4 dB 1 0
5 Locked QAM256 531000000 Hz 10.0 dBmV 39.3 dB 0 0
6 Locked QAM256 537000000 Hz 10.0 dBmV 39.3 dB 1 0
7 Locked QAM256 543000000 Hz 9.8 dBmV 39.0 dB 1 0
8 Locked QAM256 549000000 Hz 10.0 dBmV 39.2 dB 1 0
9 Locked QAM256 555000000 Hz 10.3 dBmV 39.0 dB 2 0
10 Locked QAM256 561000000 Hz 10.4 dBmV 39.0 dB 3 0
11 Locked QAM256 567000000 Hz 10.3 dBmV 38.8 dB 2 0
12 Locked QAM256 573000000 Hz 10.0 dBmV 38.6 dB 3 0
13 Locked QAM256 579000000 Hz 10.1 dBmV 38.6 dB 4 0
14 Locked QAM256 585000000 Hz 9.8 dBmV 38.5 dB 5 0
15 Locked QAM256 591000000 Hz 9.7 dBmV 38.5 dB 10 0
16 Locked QAM256 597000000 Hz 9.9 dBmV 38.6 dB 9 0
17 Locked QAM256 603000000 Hz 9.5 dBmV 38.5 dB 20 0
18 Locked QAM256 609000000 Hz 8.9 dBmV 38.4 dB 20 0
19 Locked QAM256 615000000 Hz 8.2 dBmV 38.3 dB 30 0
20 Locked QAM256 621000000 Hz 7.7 dBmV 38.2 dB 16 0
22 Locked QAM256 633000000 Hz 7.4 dBmV 38.1 dB 25 0
23 Locked QAM256 639000000 Hz 7.5 dBmV 38.2 dB 20 0
24 Locked QAM256 645000000 Hz 7.6 dBmV 38.3 dB 24 0
159 Locked Other 678000000 Hz 7.3 dBmV 36.8 dB 7918664 0


Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 3 Locked SC-QAM 23700000 Hz 6400000 Hz 38.8 dBmV
2 1 Locked SC-QAM 36500000 Hz 6400000 Hz 39.8 dBmV
3 2 Locked SC-QAM 30100000 Hz 6400000 Hz 39.3 dBmV



Current System Time: Wed Dec 6 22:59:31 2017