Community Forum

Constant disconnects

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Frequent Visitor

Constant disconnects

For the past 6 months or so I have been getting constant disconnects all day everyday.  It gets worse day by day. I can't get any work from home done due to the disconnects every 5 to 30 minutes.   Sometimes the modem resets and sometimes I just lose connection.  I removed my router from the network and have a direct wired connection to the modem.  I've called comcast for help several times but they refuse to send anyone out and blame my modem.  On the last call I had them switch to another modem with the same results, I know it's not the modem.  I had this issue a couple of years ago and comcast sent someone to check the lines and they found an issue and fixed it.  They refuse to check them now.  I have a Motorola MB8600.  Here are the errors I get all day everyday and the signal page.  

 

 

 Startup Sequence
 

 

   
   Startup Step Status Comment
 

 



  
   Acquire Downstream Channel 645000000 Hz Locked
 

 


  
   Upstream Connection OK Operational
 

 


  
   Boot State OK Operational
 

 



  
   Configuration File OK  
 

 


  
   Security Enabled BPI+
 

 


  



   Connection Status
 

 

   
   System Up Time 0 days 05h:38m:43s  
 

 


  
   Network Access Allowed  
 

 


  



   Downstream Bonded Channels
 

 

 
 

 


  
   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
   1 Locked QAM256 37 645.0 7.0 42.6 436 1041
   2 Locked QAM256 9 477.0 5.5 42.4 607 1152
   3 Locked QAM256 10 483.0 5.5 42.5 720 1084
   4 Locked QAM256 11 489.0 5.5 42.4 698 1070
   5 Locked QAM256 12 495.0 5.6 42.4 650 1089
   6 Locked QAM256 13 501.0 5.8 42.7 748 1034
   7 Locked QAM256 14 507.0 6.0 42.6 636 949
   8 Locked QAM256 15 513.0 6.1 42.6 645 982
   9 Locked QAM256 16 519.0 6.0 42.6 643 916
   10 Locked QAM256 17 525.0 6.0 42.6 476 1005
   11 Locked QAM256 18 531.0 6.2 42.8 499 984
   12 Locked QAM256 19 537.0 6.3 42.8 563 902
   13 Locked QAM256 20 543.0 6.3 42.8 510 955
   14 Locked QAM256 21 549.0 6.5 42.9 574 854
   15 Locked QAM256 22 555.0 6.5 43.0 468 932
   16 Locked QAM256 23 561.0 6.5 42.7 506 952
   17 Locked QAM256 24 567.0 6.7 42.7 488 928
   18 Locked QAM256 25 573.0 7.0 42.8 495 913
   19 Locked QAM256 26 579.0 7.0 43.0 539 856
   20 Locked QAM256 27 585.0 6.9 42.8 479 889
   21 Locked QAM256 28 591.0 7.2 43.0 483 912
   22 Locked QAM256 29 597.0 7.4 42.9 507 904
   23 Locked QAM256 30 603.0 7.3 42.9 515 823
   24 Locked QAM256 31 609.0 7.3 42.8 447 926
   25 Locked QAM256 32 615.0 7.2 42.7 457 879
   26 Locked QAM256 33 621.0 7.2 42.8 453 924
   27 Locked QAM256 34 627.0 7.1 42.8 452 906
   28 Locked QAM256 35 633.0 7.2 42.6 465 871
   29 Locked QAM256 36 639.0 7.1 42.7 464 893
   30 Locked QAM256 38 651.0 7.1 42.8 427 834
   31 Locked QAM256 39 657.0 7.2 42.8 430 884
   32 Locked QAM256 40 663.0 7.3 42.9 372 906
   33 Locked OFDM PLC 159 690.0 8.4 42.2 24722058 110



   Upstream Bonded Channels
 

 

 
 

 


  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Locked SC-QAM 5 5120 35.8 46.8
   2 Locked SC-QAM 6 5120 29.4 46.5
   3 Locked SC-QAM 7 5120 23.0 46.0
   4 Locked SC-QAM 8 5120 16.6 46.0

 

13:40:14
Sun Jun 28 2020
  Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    13:40:14
Sun Jun 28 2020
  Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    13:40:30
Sun Jun 28 2020
  Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    13:40:37
Sun Jun 28 2020
  Notice (6)   Honoring MDD; IP provisioning mode = IPv6
    13:40:46
Sun Jun 28 2020
  Notice (6)   DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    14:04:43
Sun Jun 28 2020
  Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:11:47
Sun Jun 28 2020
  Warning (5)   RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:11:47
Sun Jun 28 2020
  Warning (5)   Dynamic Range Window violation
    15:13:03
Sun Jun 28 2020
  Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:18:07
Sun Jun 28 2020
  Warning (5)   RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:18:07
Sun Jun 28 2020
  Warning (5)   Dynamic Range Window violation
    15:18:07
Sun Jun 28 2020
  Warning (5)   RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:18:07
Sun Jun 28 2020
  Warning (5)   Dynamic Range Window violation
    15:18:07
Sun Jun 28 2020
  Warning (5)   RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:18:07
Sun Jun 28 2020
  Warning (5)   Dynamic Range Window violation
    15:27:24
Sun Jun 28 2020
  Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:27:25
Sun Jun 28 2020
  Warning (5)   RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:27:25
Sun Jun 28 2020
  Warning (5)   Dynamic Range Window violation
    15:29:25
Sun Jun 28 2020
  Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:31:02
Sun Jun 28 2020
  Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:31:19
Sun Jun 28 2020
  Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:31:21
Sun Jun 28 2020
  Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:31:22
Sun Jun 28 2020
  Notice (6)   CM-STATUS message sent. Event Type Code: 6; Chan ID: 8; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:31:24
Sun Jun 28 2020
  Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:31:26
Sun Jun 28 2020
  Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:31:40
Sun Jun 28 2020
  Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:31:50
Sun Jun 28 2020
  Notice (6)   Honoring MDD; IP provisioning mode = IPv6
    15:32:00
Sun Jun 28 2020
  Notice (6)   DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:32:07
Sun Jun 28 2020
  Warning (5)   RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:32:07
Sun Jun 28 2020
  Warning (5)   Dynamic Range Window violation
    15:32:11
Sun Jun 28 2020
  Warning (5)   RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=00:40:36:4f:65:a6;CMTS-MAC=58:97:bd:2e:27:96;CM-QOS=1.1;CM-VER=3.1;
    15:32:11
Sun Jun 28 2020
  Warning (5)   Dynamic Range Window violation
Highlighted
Frequent Visitor

Re: Constant disconnects

Just wanted to provide more detail about my setup.  I do not have cable tv so there is no splitter.  The line from the poll is connected to the coax with a barrel connector straight to my modem.  The coax in the house is new and a tech came out about a year ago and replaced all of the connectors including the barrel connector.  

Highlighted
New Poster

Re: Constant disconnects

Came here to say that we've had the same experience. Xfinity is a big speed improvement over our DSL, but the only thing reliable about it is that we can expect to have the connection totally drop 1-4 times an hour. We had a tech come out and replace the line outside, but that has not done the trick. I just scheduled another call to see what else can be done. Meanwhile, I hopped on the forums to look for some answers like you.

Highlighted
Frequent Visitor

Re: Constant disconnects

When it works, I get great speeds, 340 download and about 24 uploud.  I wish I could get someone out but they are saying they can't send anyone due to Covid-19.  Strange that some people can get a tech but I cant.  If they can't come inside my house that's fine, the connectors have already been changed.  They could come check for problems on main lines.  Others in the neighborhood are having the same issue.  We are paying too much money for them not to put any effort into fixing the issue. 

Highlighted
New Poster

Re: Constant disconnects

Same issue for nearly 4 months. New modem/router was sent to us to hopefully deal with better management of ipv4 and ipv6 communication but problem has worsened. Only solution is router reset. Doing this multiple times per day is infuriating. Contacting xfinity forces an automated restart which temporarily solves connection issue. Which, in their eyes, equals a closed ticket. Have not been able to talk to an actual person for about 2 months. This is not a problem with wiring or service since cable box never loses signal. Swapped splinters and direct connected for 100% signal with no better results. Outside line is less than 6 months old to boot. Fios is in our future I’m afraid.
Highlighted
New Poster

Re: Constant disconnects

Do you see a lot of DoS attacks in your log? I get conflicting information from Netgear and other online sources on whether these are no big deal or a potential source of my issues.

Highlighted
New Poster

Re: Constant disconnects

Not sure what that means or how I would check.
Highlighted
New Poster

Re: Constant disconnects

I’ve experienced the same, everyday! New modem, tech came out, still happens!
Highlighted
Frequent Visitor

Re: Constant disconnects

This past weekend I swapped the cable my internet was on (it runs under the house) with my cable for DirecTV (it runs through the attic).  DirecTV wouldn't work at all on the cable the internet was on but the internet "worked" on the cable DirecTV was on.  The signals were a little worse and the disconnects were just as bad.  Since DirecTV wouldn't work at all on the cable under the house, I pulled some of the slack out from under the house to investigate the cable.  I found that someone  added about 6ft of cable with a barrel connector wrapped in electrical tape which was laying in the mud under the house.  I removed the extra cable and connector, cleaned the connector, and there was plenty of slack to reach the cable box.  Once this was removed, DirecTV worked fine.  I swapped this cable back to the internet and my signals were better and it worked with no disconnects from Sunday until Wednsday.  Wednsday it started disconnecting every couple of minutes again.  

 

"Tech support" is sticking to the "it's your modem" story and also saying if I had their modem they could do more diagnostics.  I just ordered one of their modems if/when it doesn't work either I'll send it back and report results here. 

 

Highlighted
Frequent Visitor

Re: Constant disconnects

As expected the Comcast modem is no different. Waiting for a call back from a tech now. I'm curious what they'll say now that they can't blame my modem.
Highlighted
New Poster

Re: Constant disconnects

Having exact same issue. We have an 18 month old Xfinity gateway modem/ router.  Also several neighbors having same problem. Technician came and said it's a problem with area cables and nodes.  I have a ticket # that is supposed to escalate us to more troubleshooting. Still waiting to hear back. 
Did you resolve your issues?