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Connection problems

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Connection problems

Hello, I'm hoping to get some help with my intermittent connection. I own a MB8600. Quite frequently, I lose connection for a few minutes at a time. I've had this problem for as long as I can remember, but sometimes it is more noticeable than others. Looking at my logs, I've always had difficulty with consecutive T3 timeouts while ranging on upstream channels. In the past, I've used coax splitters to bring down my downstream power levels to the recommended levels, but that seemed to make my connection more unreliable. So now, My modem is connected as directly as possible to the Comcast coaxial line that enters my home. Although it throws out a ton of errors on my modem log, at least my connection is usable for my most important needs (not for online gaming though). I am hoping to be referred to a Comcast technician to evaluate my line quality from their end.

 

Here are my signals: 

Connection
   Startup Sequence    
   Startup Step Status Comment

  
   Acquire Downstream Channel 567000000 Hz Locked
  
   Upstream Connection OK Operational
  
   Boot State OK Operational

  
   Configuration File OK  
  
   Security Enabled BPI+
  


   Connection Status    
   System Up Time 1 days 03h:50m:38s  
  
   Network Access Allowed  
  


   Downstream Bonded Channels  
  
   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (d Corrected Uncorrected
   1 Locked QAM256 39 567.0 8.9 39.2 2124 4326
   2 Locked QAM256 17 435.0 7.1 38.7 3397 4877
   3 Locked QAM256 18 441.0 7.3 38.7 3452 5324
   4 Locked QAM256 19 447.0 7.6 38.7 3428 4863
   5 Locked QAM256 20 453.0 8.1 38.7 3214 5315
   6 Locked QAM256 21 459.0 8.3 38.7 3082 4818
   7 Locked QAM256 22 465.0 8.6 38.5 3148 5122
   8 Locked QAM256 23 471.0 9.0 38.6 2963 5054
   9 Locked QAM256 24 477.0 9.5 38.9 2812 4766
   10 Locked QAM256 25 483.0 9.7 38.9 2775 4849
   11 Locked QAM256 26 489.0 10.0 38.9 2671 4759
   12 Locked QAM256 27 495.0 10.4 39.0 2622 4679
   13 Locked QAM256 28 501.0 10.4 38.9 2532 4707
   14 Locked QAM256 29 507.0 10.5 39.2 2393 4525
   15 Locked QAM256 30 513.0 10.2 39.0 2525 4591
   16 Locked QAM256 31 519.0 9.9 39.2 2400 4520
   17 Locked QAM256 32 525.0 9.9 39.3 2147 4442
   18 Locked QAM256 33 531.0 10.0 39.1 2142 4346
   19 Locked QAM256 34 537.0 9.8 39.0 2165 4606
   20 Locked QAM256 35 543.0 9.4 38.9 2256 4335
   21 Locked QAM256 36 549.0 8.1 38.3 2130 4149
   22 Locked QAM256 37 555.0 8.6 38.7 2050 4268
   23 Locked QAM256 38 561.0 9.1 39.0 1919 4094
   24 Locked QAM256 40 573.0 8.9 39.1 1956 4116
   25 Locked QAM256 41 579.0 8.7 39.1 1883 4299
   26 Locked QAM256 42 585.0 8.8 39.2 1888 4314
   27 Locked QAM256 43 591.0 8.5 39.1 1879 4019
   28 Locked QAM256 44 597.0 8.5 39.2 1960 4156
   29 Locked QAM256 45 603.0 8.1 38.9 1867 4015
   30 Locked QAM256 46 615.0 7.7 39.1 1752 4075
   31 Locked QAM256 47 621.0 7.9 39.1 1763 3887
   32 Locked OFDM PLC 48 685.0 7.4 15.1 7632608 0

 

   Upstream Bonded Channels  
  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Locked SC-QAM 1 5120 17.3 38.8
   2 Locked SC-QAM 2 5120 23.7 38.8
   3 Locked SC-QAM 3 5120 30.3 38.3
   4 Locked SC-QAM 4 5120 36.7 48.8

 

 

Here is my log:

 

16:31:33
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:31:33
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:32:21
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:32:21
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:33:21
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:33:21
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:33:21
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:33:21
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:33:21
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:33:21
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:33:21
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:33:21
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:35:21
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:35:21
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:35:21
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:35:21
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:35:21
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:35:21
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:35:22
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:35:22
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:35:22
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:35:22
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:35:22
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:35:22
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:35:22
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:35:22
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:36:09
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:36:09
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:36:09
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:36:09
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
    16:36:53
Mon Sep 2 2019
  Warning (5)   RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4e:8d:6d;CMTS-MAC=00:01:5c:63:b6:4d;CM-QOS=1.1;CM-VER=3.1;
    16:36:53
Mon Sep 2 2019
  Warning (5)   Dynamic Range Window violation
Gold Problem Solver

Re: Connection problems

The downstream signals look OK, but the upstream levels on channel#4 are out of whack compared to channels #1-3. The levels on all four channels should be about the same. And the error log "Dynamic Range Window" and "Commanded Power Exceeds" errors both suggest a problem in the connection to Comcast's network affecting the upstream channels.

 

If you want to troubleshoot this yourself, please see Connection Troubleshooting Tips. Problems with Internet service are often due to poor coax connections between your equipment and Comcast's network, usually in or near your home.

If you can't find the problem or you'd rather have Comcast do the troubleshooting, call them at the phone number on your bill or 1-800-Comcast, or or use one of the options on https://www.xfinity.com/support/contact-us/. It isn't likely they can fix this remotely, and if not insist they send a tech out to identify the cause and correct it.

If the tech finds bad coax, splitters, amplifiers, or connections in your home (even if Comcast originally supplied them) you'll probably have to pay for the visit unless you have their Service Protection Plan (https://www.xfinity.com/support/articles/service-protection-plan, closed to customers that don't already have it). If the trouble is due to a faulty Comcast rental device, or anything outside your home, you shouldn't be charged.