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Rookie

Connectivity Problem, Maxx Upgrade soon

Hi TWC,

 

I own a Motorola SB6141 modem and currently on the 30/5 plan in Greensboro, NC.  (Zip is 27358).

 

Here's the problem.  Over the past month, I've noticed occasional/intermmitent slow downs not related to peak time.  I've narrowed down the problem to the cable modem: typically, the highest downstream channel seems really far off from the others in terms of power level and correctable/uncorrectable codewords.  In fact, the power level has always been exactly 0 dBmV for this one channel -- which is never the case for the others.  The result is that speed tests and latency are all affected (high ping times, usually <1mb download).  Upload speed is NOT affected.

 

If I reboot the modem, all is fine for awhile -- the modem seems to lock on to a different set of channels, and all seem equal in regards to stats.  Then, I'll notice another slowdown typically within 24 hours.  Looking at the cable modem signal page, once again typically the highest channel is really far off from the others, and at some point the modem must've acquired the new channel.

 

This problem will correct itself if I wait long enough for the modem to acquire a new downstream channel that seems to be problematic.  Or, I can reboot it.  This is frustrating to do.

 

I just learned that there are upgrades pending for the area.  Since I'll need a new modem on the new speeds as my current only supports 8x4, I can either wait until Maxx upgrade is complete if it is imminent or get a replacement sooner. 

 

While I certainly could be wrong, I don't think the problem is with the cable modem -- any insight would be appreciated.  

 

 

3 REPLIES 3
Expert

Re: Connectivity Problem, Maxx Upgrade soon

Don't reset the modem, post the sig level and error log pagex.

what speed  you pay for and your zip code

 

Rookie

Re: Connectivity Problem, Maxx Upgrade soon

OK -- took a few days for the problem to resurface so was hoping it was resolved, but occurred again yesterday. Speed test shows ~1mb down, full 5 to 6mb up. Here's the signal page.  Whenever this problem happens, the high channel (in this case, 16) always shows a power level of 0 dBmV, and as you can see the uncorrectables are very high.

 

 

Downstream Bonding Channel Value

Channel ID10 12 13 16 
Frequency555000000 Hz 561000000 Hz 591000000 Hz 609000000 Hz 621000000 Hz 627000000 Hz 645000000 Hz 
Signal to Noise Ratio37 dB 37 dB 38 dB 37 dB 38 dB 37 dB 36 dB 
Downstream ModulationQAM256 QAM256 QAM256 QAM256 QAM256 QAM256 QAM256 
Power Level
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading
-5 dBmV  -4 dBmV  -5 dBmV  -4 dBmV  -4 dBmV  -4 dBmV  0 dBmV  

 

Upstream Bonding Channel Value
Channel ID
Frequency37000000 Hz 24200000 Hz 30600000 Hz 19400000 Hz 
Ranging Service ID1199 1199 1199 1199 
Symbol Rate2.560 Msym/sec 5.120 Msym/sec 5.120 Msym/sec 2.560 Msym/sec 
Power Level44 dBmV 42 dBmV 43 dBmV 42 dBmV 
Upstream Modulation[3] QPSK
[3] 16QAM
 
[3] QPSK
[1] 16QAM
[2] 64QAM
 
[3] QPSK
[1] 16QAM
[2] 64QAM
 
[3] QPSK
[2] 16QAM
 
Ranging StatusSuccess Success Success Success 

 

Signal Stats (Codewords)Bonding Channel Value
Channel ID10 12 13 16 
Total Unerrored Codewords5801427355 5800699244 5065471213 4749287992 4279142979 3434427197 3178032328 
Total Correctable Codewords56 86 141 196 381 
Total Uncorrectable Codewords490 547 2416 5360 5045 6448 59403 

 

 

 

This is about 15 hours later after everything has been running fine:

 

Downstream Bonding Channel Value

Channel ID10 12 13 
Frequency555000000 Hz 561000000 Hz 579000000 Hz 585000000 Hz 591000000 Hz 609000000 Hz 621000000 Hz 627000000 Hz 
Signal to Noise Ratio37 dB 37 dB 37 dB 37 dB 37 dB 37 dB 38 dB 37 dB 
Downstream ModulationQAM256 QAM256 QAM256 QAM256 QAM256 QAM256 QAM256 QAM256 
Power Level
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading
-4 dBmV  -3 dBmV  -4 dBmV  -4 dBmV  -4 dBmV  -3 dBmV  -3 dBmV  -3 dBmV  

 

Upstream Bonding Channel Value
Channel ID
Frequency37000000 Hz 24200000 Hz 30600000 Hz 19400000 Hz 
Ranging Service ID1201 1201 1201 1201 
Symbol Rate2.560 Msym/sec 5.120 Msym/sec 5.120 Msym/sec 2.560 Msym/sec 
Power Level45 dBmV 43 dBmV 44 dBmV 42 dBmV 
Upstream Modulation[3] QPSK
[3] 16QAM
 
[3] QPSK
[1] 16QAM
[2] 64QAM
 
[3] QPSK
[1] 16QAM
[2] 64QAM
 
[3] QPSK
[2] 16QAM
 
Ranging StatusSuccess Success Success Success 

 

Signal Stats (Codewords)Bonding Channel Value
Channel ID10 12 13 
Total Unerrored Codewords2322756525 2322004392 2043467077 2043506989 2043430422 1977617848 1599695677 1866078524 
Total Correctable Codewords32 36 48 129 100 125 
Total Uncorrectable Codewords554 544 1952 1988 2084 2641 8427 2618 

 

 

And finally, the log file.  The cable modem reboot occured around 12:45am or so on 5/14. 

 

TimePriorityCodeMessage

May 14 2016 00:47:536-NoticeI401.0TLV-11 - unrecognized OID;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
May 14 2016 00:47:535-WarningZ00.0MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
May 14 2016 00:47:306-NoticeI401.0TLV-11 - unrecognized OID;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
May 14 2016 00:47:305-WarningZ00.0MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:156-NoticeN/ACable Modem Reboot from GUI/Configuration page ;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
May 13 2016 23:25:545-WarningT202.0Lost MDD Timeout;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
May 13 2016 23:25:545-WarningN/ADS Partial Service Fallback: MDD Lost-> CM in DOCSIS 3.0 Recovery Mode ;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
May 13 2016 16:49:135-WarningT202.0Lost MDD Timeout;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
May 13 2016 16:49:135-WarningN/ADS Partial Service Fallback: MDD Lost-> CM in DOCSIS 3.0 Recovery Mode ;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
May 13 2016 16:49:135-WarningT202.0Lost MDD Timeout;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
May 13 2016 16:49:135-WarningN/ADS Partial Service Fallback: MDD Lost-> CM in DOCSIS 3.0 Recovery Mode ;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
May 12 2016 13:18:236-NoticeI401.0TLV-11 - unrecognized OID;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
May 12 2016 13:18:235-WarningZ00.0MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
May 12 2016 13:18:016-NoticeI401.0TLV-11 - unrecognized OID;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
May 12 2016 13:18:015-WarningZ00.0MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:146-NoticeN/ACable Modem Reboot from GUI/Configuration page ;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.0;
May 12 2016 01:06:355-WarningT202.0Lost MDD Timeout;CM-MAC=dc:45:17:xxx;CMTS-MAC=00:17:10:8c:7f:a2;CM-QOS=1.1;CM-VER=3.0;

 

 

Expert

Re: Connectivity Problem, Maxx Upgrade soon

You have bad coax connections, chewed cable, too many splitters or open ports. Call twc out on intermittents, partial downstream service probably due to broadcast TV ingress.

 It can't be fixed over the phone and another modem won't solve coax issues

Needs a tech out.