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Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

AC2k
Frequent Visitor

Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

Modem: Motorola MB8600

 

I also have an Arris MB6183 i can try if anyone thinks that might work better?

 

I get this every day and my internet drops.  Already had a tech out who basically alluded that there was nothing that could be done because of how the cable heats up when it is hot outside, combined with possibly poor wiring in my building.  Does this sound right?  There's really nothing I can do to prevent these small outages? (It goes down for a few seconds then comes back, but knocks me off my employer's VPN when it does and kills my IP phone calls.  I think my colleagues are getting tired of me always dropping out of meetings.)

 

This has been an issue since I've lived at the address (2+ years).  For a while I had an amp with active return on the line and didn't experience any issues for a long time. Then these short drop-outs started occurring about a month ago, which is why I had the tech come out.  I haven't put the amp back on the line, but the dropouts were occurring even I did have it connected.

 

I have NO SPLITTERS on the line at all.  It goes from the wall plate (which the tech also checked behind and said it was fine) straight to the modem.  Switching coax cables doesn't help.

 

Tech said my signal levels were OK.

(Address info removed from the log for public posting)

 

Event Log
   Log
 

 

 
 

 


  
   Time  Priority  Description 
   09:51:13
Fri Aug 7 2020
 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;
   09:54:04
Fri Aug 7 2020
 Critical (3) Unicast Ranging Received Abort Response - Re-initializing MAC;
   09:54:09
Fri Aug 7 2020
 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;
   09:54:34
Fri Aug 7 2020
 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;

 

Startup StepStatusComment
 

 



  
   Acquire Downstream Channel561000000 HzLocked
 

 


  
   Upstream ConnectionOKOperational
 

 


  
   Boot StateOKOperational
 

 



  
   Configuration FileOK 
 

 


  
   SecurityEnabledBPI+
 

 


  



   Connection Status
 

 

  
   System Up Time4 days 16h:59m:43s 
 

 


  
   Network AccessAllowed 
 

 


  



   Downstream Bonded Channels
 

 

 
 

 


  
   ChannelLock StatusModulationChannel IDFreq. (MHz)Pwr (dBmV)SNR (dB)CorrectedUncorrected
   1LockedQAM25625585.04.540.427883324
   2LockedQAM2569483.03.940.236992943
   3LockedQAM25610489.04.140.235763168
   4LockedQAM25611495.04.240.237693606
   5LockedQAM25612507.04.540.436853671
   6LockedQAM25613513.04.640.334023347
   7LockedQAM25614519.04.640.334743357
   8LockedQAM25615525.04.540.432892952
   9LockedQAM25616531.04.540.434173380
   10LockedQAM25617537.04.640.531863187
   11LockedQAM25618543.04.640.533103528
   12LockedQAM25619549.04.340.430773178
   13LockedQAM25620555.04.340.632953625
   14LockedQAM25621561.04.140.730453236
   15LockedQAM25622567.04.040.534903860
   16LockedQAM25623573.04.040.429763621
   17LockedQAM25624579.04.440.530764257
   18LockedQAM25626591.04.640.527373472
   19LockedQAM25627597.04.740.625092776
   20LockedQAM25628603.04.640.526563236
   21LockedQAM25629609.04.340.424463036
   22LockedQAM25630615.04.140.326353584
   23LockedQAM25631621.04.340.423683185
   24LockedQAM25632627.04.540.521793155
   25LockedQAM25633633.04.740.319842513
   26LockedQAM25634639.04.940.518932402
   27LockedQAM25635645.05.540.618332312
   28LockedQAM25636651.05.740.519422112
   29LockedQAM25637657.05.840.517931906
   30LockedQAM25638663.05.640.315501679
   31LockedQAM25639669.05.540.415971608
   32LockedQAM25640675.05.040.016361552
   33LockedOFDM PLC159690.06.339.211970



   Upstream Bonded Channels
 

 

 
 

 


  
   ChannelLock StatusChannel TypeChannel IDSymb. Rate (Ksym/sec)Freq. (MHz)Pwr (dBmV)
   1LockedSC-QAM1512016.246.0
   2LockedSC-QAM2512022.746.5
   3LockedSC-QAM3512029.247.0
   4LockedSC-QAM4512035.748.0
   5LockedSC-QAM5128041.248.5

 

AC2k
Frequent Visitor

Re: Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

I do see that my downstream SNRs are too high, meaning too much noise on the line(?).  I don't think there is anything I can do to affect that though, is there?  Are some modems more susceptible to noise like this than others?

EG
Expert

Re: Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

Nope. The SNR can never be "too high". Higher is better ! Higher means less noise, not more noise.

 

If anything, the upstream power is on the high side and it may be intermittently fluctuating even higher to out of spec levels. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.



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.
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AC2k
Frequent Visitor

Re: Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

Higher is better (SNR)... ahhh yes... my bad.  

 

Going by the "Internet Troubleshooting Tips" post, my upstream levels are right on the line, so I suspect maybe that is indeed the issue.  Maybe I will throw the amp back on the line which should pull those down quite a bit.  The tech that came out indicated those levels should be ok, but clearly I am still having the same issue.

 

And, as I mentioned in my post, I have 0 splitters on the line.  The tech replaced the one I had on there, but in the days that followed I saw the upstream levels getting up to 55, so I removed the splitter, which seems to keep them right under or at  50.

 

Other than adding the amp I'm not sure what else I can do.  I've already had a tech out here and I have no splitters to remove. 

EG
Expert

Re: Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

I would try the amp !

 

As an FYI, bear in mind that if the premises facing techs can not find or fix a problem at your home, it is they who are responsible for escalating it to their line / network / maintenance dept. techs. The problem may lie beyond your home in the local neighborhood infrastructure somewhere but it is their S.O.P. to start at the home.

Good luck with it !



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!
AC2k
Frequent Visitor

Re: Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

Thanks!  That is good to know.  Sounds like I'll have to call in again if the amp doesn't help me.

 

I wish it were easier to contact comcast for service.  I just end up in a never-ending loop with the chatbot and when I call in I always have to re-start my modem, wait ten minutes for a message that never comes, call back in, restart my modem again, wait another ten minutes for a message that never comes, then call back in again, then at that point I get added to the queue to be put on hold for the next available representative.  It's such a waste of my time.

 

But that is a completely separate issue, of course.

EG
Expert

Re: Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

Sorry. I feel your pain ! I don't work for them or make policy.



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!
AC2k
Frequent Visitor

Re: Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

On the plus side, once I do get through to a rep they are generally friendly, sympathetic, and seem like they want to do whatever they can to help.

 

Comcast just needs to adjust their chatbot and IVR.  (sigh)

AC2k
Frequent Visitor

Re: Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

Looks like the amp has made my downstream levels too high and my upstream levels too low.  Should I try a less-powerful amp maybe?

 

 Downstream Bonded Channels
 

 

 
 

 


  
   ChannelLock StatusModulationChannel IDFreq. (MHz)Pwr (dBmV)SNR (dB)CorrectedUncorrected
   1LockedQAM25617537.018.340.100
   2LockedQAM2561423.017.740.200
   3LockedQAM2562435.017.840.000
   4LockedQAM2563447.017.640.000
   5LockedQAM2564453.017.539.800
   6LockedQAM2565459.017.439.700
   7LockedQAM2566465.017.339.600
   8LockedQAM2567471.017.539.600
   9LockedQAM2568477.017.839.800
   10LockedQAM2569483.018.139.800
   11LockedQAM25610489.018.339.600
   12LockedQAM25611495.018.339.800
   13LockedQAM25612507.018.439.800
   14LockedQAM25613513.018.539.800
   15LockedQAM25614519.018.439.900
   16LockedQAM25615525.018.339.900
   17LockedQAM25616531.018.239.900
   18LockedQAM25618543.018.340.100
   19LockedQAM25619549.018.040.000
   20LockedQAM25620555.018.040.100
   21LockedQAM25621561.018.040.300
   22LockedQAM25622567.018.140.100
   23LockedQAM25623573.018.140.100
   24LockedQAM25624579.018.540.100
   25LockedQAM25625585.018.440.000
   26LockedQAM25626591.018.540.100
   27LockedQAM25627597.018.640.000
   28LockedQAM25628603.018.340.100
   29LockedQAM25629609.017.940.000
   30LockedQAM25630615.017.740.000
   31LockedQAM25631621.017.739.900
   32LockedQAM25632627.017.839.700
   33LockedOFDM PLC159690.020.138.800



   Upstream Bonded Channels
 

 

 
 

 


  
   ChannelLock StatusChannel TypeChannel IDSymb. Rate (Ksym/sec)Freq. (MHz)Pwr (dBmV)
   1LockedSC-QAM1512016.231.5
   2LockedSC-QAM2512022.731.5
   3LockedSC-QAM3512029.232.0
   4LockedSC-QAM4512035.732.0
   5LockedSC-QAM5128041.233.0
AC2k
Frequent Visitor

Re: Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

Had to remove the amp.  It went crazy with the amp on the line.  I ordered an amp with way less gain but it won't get here for a while.  I'll report back after that with status in case anyone else is having a similar issue and trying to solve it a similar way.

 

I'm not exactly sure what to say to comcast when/if I do end up contacting them again, other than "already had a tech out.  Still doesn't work."  I'm not sure what actually triggers the escalation process.  It's a tough one to solve because of course the problem never manifests itself when a tech is actually here.

AC2k
Frequent Visitor

Re: Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

Got the new amp which is 7db.  Did not fix the problem, but now my internet only drops 1-2 times per day as opposed to 10+ times per day.  It's an improvement, but not a fix, and I still see the same errors coming through the modem log when the problem occurs.

 

Oh yes, and I also replaced the modem.  And the cabling. 

 

I think I'll just move.  I can only get Xfinity in my current lcoation but (another provider) is available almost everywhere else in the same city.  It's probably easier than trying to get this fixed.

AC2k
Frequent Visitor

Re: Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

So I was able to get back in touch with Xfinity support and tried to ask for a next-support-tier escalation, since the tech couldn't find anything wrong.  They basically told me no further troubleshooting could be done unless I rent a modem from Xfinity, even though I've treid 3 different supposedly "xfinity-certified" modems.

 

$14 a month for a modem rental when a good modem costs about $70 is highway robbery. 

 

So they are sending me a modem.

 

I have 0 expectation that this will make any difference.  The problem is clearly not on my side of the wall.  I don't know how to get someone to listen to me.  The guy kept talking about WiFi and how I'll be able to see what devices are conencted to Wifi (with teh Xfinity Modem) even though I said multiple times I'm not using WiFi.

 

But I guess it is policy to not troubleshoot further unless you get your modem from them, so I guess I have to pay more money to prove that the problem is not with the modems.

AC2k
Frequent Visitor

Re: Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

Have installed the Xfinity gateway to replace my Arris modem.  (Xfinity modem is also made by Arris, apparently).

 

Can't figure out how to see the error log, but the signal levels do look slightly better.  About +3db for downstream and about +45db for upstream.  No amp or antyhing on the line now - I used the xfinity-provided cable to conect directly from the wall-plate to the gateway device.

 

I'm already seeing the codeword errors, but service has not dropepd yet.  It's only been a few hours though.

 

One thing I will say is that this gateway device is excruciatingly slow to log in to and navigate around.  Not sure if that means anything.  It does eventualy bring up the requested pages, but it's not snappy like my personally owned modems were.  I have enough time to go pour a cup of coffee while i'm waiting for the darned page to load. I'm plugging my laptop directly into the gateway to manage it, so its not something else on my network affecting the response time.

 

I'll be calling Xfiity back as soon as my conenction starts dropping again, but now I can't find the actual errors to relay to anyone.

AC2k
Frequent Visitor

Re: Started Unicast Maintenance Ranging - No Response received (Daily internet service drops)

As expected, no change at all with the Xdfinity-provided equipment.  Internet still drops, and I can see thousands of uncorrectible codewords in the network status page.

 

Called back in.  Talked to a woman for what seemed like a long time (maybe 20-30 minutes?) who ran me through the modem reset nonsense again.

 

She ccouldn't help.  Tranferred me to a guy on the other side of the country who seemed very knwoedgeable and very willing to help.  He didn't know I had already talked to someone so of course I had to go through the whole spiel again.  He seemed genunely interested in helping but said he could not see my modem information and he needed to get someone on the line with us in my state.

 

Then I got put back into the regular call queue.  The next rep who picked up (after another period of time on hold) also had no idea I'd already talked to two other people.  She said "Oh I'm looking up your account" and then I got some hold music, then an extremely loud buzzing, then hung up.

 

I called back and then started at squarte one with "we're resetting your modem."

 

My tolerance level has been reached.  I will be cancelling my Xfinity service. I have wasted enough of my time and money on this nonsense.