U

Visitor

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9 Messages

Saturday, January 28th, 2023 1:34 AM

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Motorola MB8611 modem frequently loses connection to Xfinity/reboots (yeah same here)

I seem to be able to relate to nearly everything people have posted in ‎Motorola MB8611 modem frequently loses connection to Xfinity/reboots | Xfinity Community Forum.

I purchased my MB8611 last April to go along with a speed upgrade after seeing that the equipment is Comcast/Xfinity certified. The line to my house was unprotected and poor and so crew came out and replaced it about a month later. (Great crew BTW.) Since then we've never achieved the target speeds, but it was an improvement. (Best I can do is 320Mbps down out of expected 1Gbps plan.) But so unreliable and unpredictable. We can go a couple of days without seeing an issue and then we'll have several drops in a couple hours. I cannot relate the drops to any usage patterns in our household.

I have chatted with tech support a number of times including two days ago. On multiple occasions a tech has been scheduled and then I get a message the next morning that someone has reviewed the issue and made a correction -- would I like to cancel my appointment. That "fix" usually seems to last around 24 hours or it is coincidence. The last cycle of this was two days ago. I did not cancel my appointment as it was another day out. Sure enough there were three drops the morning before appointment. (My router's system log has a very regular pattern when the drop happens; so, I now can so how often it happens even if I no one is actively using internet.)

A senior technician arrived and did basic line test for noise and claimed all is good. I mentioned that others have suggested that troubles arise from neighbors with older/faulty equipment. I do know that no one else has tried to update in last 5+ years and definitely will have the same unshielded lines to their homes. One said they think reliability has gone down in the last 2 years. Tech said others don't seem to have a problem so nothing he can do for me without seeing the issue. And so concluded that it must be my modem. I asked that he be sure to get that to me in email or such so I can get Motorola to replace it but I haven't seen that so far.

What I can say is that a prior tech did see the drop while present using their own equipment. They also found that cable coming to the wall panel by modem was bent and shielding had been damaged. Pretty sure this was after checking line noise and thinking things were fine. So, they fixed that and expected that to be the end of it. But I don't know how techs can expect customers to demonstrate the issue while they are there. In my opinion Comcast needs to be monitoring better to be able to detect problems. The tech I most recently spoke to didn't really know what data Comcast actually has access to.

To continue my situation, I engaged Motorola support and shared modem data. The rep doesn't understand how the Comcast tech can say things were good based on the connection report from the modem that I shared. The rep did confirm that once a sufficient number of errors are reached the modem will restart itself. That is designed behavior. (Unfortunately, the device doesn't keep a specific log that says it restarted itself to deal with that, but from the errors the rep is very confident.) So Motorola is going to replace the modem but doesn't expect it will make a difference. (I will incur a shipping cost to return the maybe defective or maybe perfectly fine device. :( )

I am hoping that someone can confirm from my connection report whether there is a line issue as Motorola says or it could be the device as Comcast speculates:

Connection Status

 

   System Up Time

0 days 01h:48m:41s

  

   Network Access

Allowed

  

 

 

   Downstream Bonded Channels

 

  

   Channel

Lock Status

Modulation

Channel ID

Freq. (MHz)

Pwr (dBmV)

SNR (dB)

Corrected

Uncorrected

   1

Locked

QAM256

25

579.0

1.9

38.1

71

2

   2

Locked

QAM256

13

495.0

2.0

38.5

70

0

   3

Locked

QAM256

14

507.0

1.8

38.3

70

2

   4

Locked

QAM256

15

513.0

1.6

38.2

71

0

   5

Locked

QAM256

16

519.0

1.5

38.1

77

12

   6

Locked

QAM256

17

525.0

1.6

38.1

63

4

   7

Locked

QAM256

18

531.0

1.7

38.3

62

7

   8

Locked

QAM256

19

543.0

1.8

38.3

59

5

   9

Locked

QAM256

20

549.0

1.8

38.3

56

0

   10

Locked

QAM256

21

555.0

1.7

38.1

78

0

   11

Locked

QAM256

22

561.0

1.7

38.1

66

5

   12

Locked

QAM256

23

567.0

1.7

38.0

66

1

   13

Locked

QAM256

24

573.0

1.8

38.1

71

3

   14

Locked

QAM256

26

585.0

1.9

37.9

69

1

   15

Locked

QAM256

27

591.0

1.8

37.9

54

0

   16

Locked

QAM256

28

597.0

1.8

37.8

48

0

   17

Locked

QAM256

29

603.0

1.6

37.8

60

0

   18

Locked

QAM256

30

609.0

1.7

37.9

64

2

   19

Locked

QAM256

31

615.0

1.8

37.9

51

0

   20

Locked

QAM256

32

621.0

1.9

37.9

40

0

   21

Locked

QAM256

33

627.0

2.0

37.9

49

0

   22

Locked

QAM256

34

633.0

1.7

37.6

50

0

   23

Locked

QAM256

35

639.0

1.6

37.8

49

1

   24

Locked

QAM256

36

645.0

1.9

37.8

53

1

   25

Locked

QAM256

37

651.0

1.9

37.8

52

0

   26

Locked

QAM256

38

657.0

2.0

37.9

56

1

   27

Locked

QAM256

39

663.0

2.2

38.1

52

0

   28

Locked

QAM256

40

669.0

1.9

37.9

4102

601

   29

Locked

QAM256

41

675.0

2.1

37.5

231022

247517

   30

Locked

QAM256

42

681.0

2.2

38.0

102487

177802

   31

Locked

QAM256

43

687.0

1.8

37.9

195347

469543

   32

Locked

QAM256

44

693.0

1.9

37.8

47

0

   33

Locked

OFDM PLC

159

722.0

0.8

37.8

32577656

7

And here are the results 2.5 hours later:

Connection Status
   System Up Time 0 days 04h:16m:37s
   Network Access Allowed


   Downstream Bonded Channels
   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
   1 Locked QAM256 25 579.0 1.7 37.9 71 2
   2 Locked QAM256 13 495.0 1.8 38.3 70 0
   3 Locked QAM256 14 507.0 1.6 38.2 70 2
   4 Locked QAM256 15 513.0 1.5 38.1 71 0
   5 Locked QAM256 16 519.0 1.4 38.0 77 12
   6 Locked QAM256 17 525.0 1.4 38.2 63 4
   7 Locked QAM256 18 531.0 1.5 38.3 62 7
   8 Locked QAM256 19 543.0 1.6 38.0 59 5
   9 Locked QAM256 20 549.0 1.6 38.0 56 0
   10 Locked QAM256 21 555.0 1.6 38.0 78 0
   11 Locked QAM256 22 561.0 1.6 38.0 66 5
   12 Locked QAM256 23 567.0 1.6 38.0 66 1
   13 Locked QAM256 24 573.0 1.7 37.9 71 3
   14 Locked QAM256 26 585.0 1.7 38.1 69 1
   15 Locked QAM256 27 591.0 1.6 37.9 54 0
   16 Locked QAM256 28 597.0 1.6 37.8 48 0
   17 Locked QAM256 29 603.0 1.5 37.8 60 0
   18 Locked QAM256 30 609.0 1.6 37.7 64 2
   19 Locked QAM256 31 615.0 1.7 37.9 51 0
   20 Locked QAM256 32 621.0 1.7 37.8 40 0
   21 Locked QAM256 33 627.0 1.8 37.6 49 0
   22 Locked QAM256 34 633.0 1.6 37.5 50 0
   23 Locked QAM256 35 639.0 1.4 37.6 49 1
   24 Locked QAM256 36 645.0 1.7 37.8 53 1
   25 Locked QAM256 37 651.0 1.7 37.7 52 0
   26 Locked QAM256 38 657.0 1.8 37.8 56 1
   27 Locked QAM256 39 663.0 2.0 37.7 52 0
   28 Locked QAM256 40 669.0 1.8 37.9 4102 601
   29 Locked QAM256 41 675.0 1.9 37.7 231473 247519
   30 Locked QAM256 42 681.0 2.0 37.9 102487 177802
   31 Locked QAM256 43 687.0 1.7 37.8 195347 469543
   32 Locked QAM256 44 693.0 1.7 37.8 47 0
   33 Locked OFDM PLC 159 722.0 0.6 37.7 88110008 7


   Upstream Bonded Channels
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
   1 Locked SC-QAM 1 2560 10.4 40.0
   2 Locked SC-QAM 2 5120 16.4 39.5
   3 Locked SC-QAM 3 5120 22.8 40.0
   4 Locked SC-QAM 4 5120 29.2 40.5
   5 Locked SC-QAM 5 5120 35.6 40.0
   6 Locked SC-QAM 6 2560 40.4 42.0

Additional things that I wonder. Why is there a repeated pattern of contacting support and getting a tech service scheduled to then have someone else say they have fixed the issue? Since this repeats across customers isn't there something better that can be done? These modems are Xfinity Certified .. should that certification be rescinded? What is the deal?

There is a hint at the end of thread I posted that there is a known issue on Comcast side that just isn't fully being acknowledged. The Motorola rep kinda hinted at the same.

Visitor

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44 Messages

2 years ago

Comcast has no incentive to  help remediate the issue because their fallback is 'it's not our equipment'.

I had 2 techs come out to tell me also they don't get 'invited' to any network engineering meetings or rollouts calls.

That just tells me that Comcast is a disjointed behemoth that can never be customer centric.

BTW - I have all of your symptoms & am debating if I should take Moto up on their replacement warranty.

I am staring @ my email ticket with them & don't know if i should replace perfectly good hardware for same but new hardware or $25 shipping cost.

(edited)

Visitor

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6 Messages

2 years ago

Like many others I have the same story with the MB8611. Same reboots. Same Xfinity calls. Same Xfinity tech visits. Same calls to Motorola. But today (jan 31) after what seemed like an unusally good network day... I noticed that my MB8611 software has been downgraded to 19.2.18. And the connection has been stable for 14 hours. This is after an "upgrade" yesterday evening from version 19.2.20 to 19.3.7 that sent the modem into a tailspin with even more frequent reboots.

I hope this downgrade is an honest effort to fix the issue that so many customers are having.

I am curious if anyone else has seen a downgrade of their MB8611 software.

(edited)

Visitor

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6 Messages

Feb 10 update:

After 54 hours up from Jan 31 to Feb2 the modem rebooted again. The modem was then back to software 19.2.20. In my support ticket with Motorola the tech said "The software version Comcast should push to your modem is 19.2.18. I don't really know why they changed it back to the 19.2.20 version. Please power off the modem for 30 seconds, power it on, and check if the software version is still 19.2.20 after the boot cycle has been completed. If no change you should contact Comcast and ask them to update your firmware with the 19.2.18 version."

I didn't pursue it (and left it at 19.2.20) mostly because dealing with Xfinity support is time consuming (among other things) and the number of reboots was tolerable since only two occurred during business hours. As of the reboot at 9:20 this morning, the software/firmware is back to 19.2.18. 

Time Not Established Critical (3)       SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
10:47:01 Thu Feb 2 2023     Critical (3)        UCD invalid or channel unusable;
Time Not Established Critical (3)       SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
22:47:03 Thu Feb 2 2023     Critical (3)        UCD invalid or channel unusable;
Time Not Established Critical (3)       SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
19:10:20 Fri Feb 3 2023     Critical (3)        UCD invalid or channel unusable;
Time Not Established Critical (3)       SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
07:51:39 Sun Feb 5 2023     Critical (3)        UCD invalid or channel unusable;
Time Not Established Critical (3)       SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
02:48:15 Tue Feb 7 2023     Critical (3)        UCD invalid or channel unusable;
Time Not Established Critical (3)       SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
Time Not Established Critical (3)       Started Unicast Maintenance Ranging - No Response received - T3 time-out;
Time Not Established Critical (3)       Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;
16:10:51 Tue Feb 7 2023     Critical (3)        UCD invalid or channel unusable;
Time Not Established Critical (3)       SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
20:09:31 Tue Feb 7 2023     Critical (3)        UCD invalid or channel unusable;
Time Not Established Critical (3)       SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
Time Not Established Critical (3)       Started Unicast Maintenance Ranging - No Response received - T3 time-out;
Time Not Established Critical (3)       Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;
20:35:47 Tue Feb 7 2023     Critical (3)        UCD invalid or channel unusable;
Time Not Established Critical (3)       SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
12:53:03 Thu Feb 9 2023     Critical (3)        UCD invalid or channel unusable;
Time Not Established Critical (3)       SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
Time Not Established Critical (3)       Started Unicast Maintenance Ranging - No Response received - T3 time-out;
Time Not Established Critical (3)       Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;
06:11:57 Fri Feb 10 2023        Critical (3)        UCD invalid or channel unusable;
Time Not Established Critical (3)       SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;
Time Not Established Critical (3)       Started Unicast Maintenance Ranging - No Response received - T3 time-out;
Time Not Established Critical (3)       Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;
Time Not Established Notice (6)     Honoring MDD; IP provisioning mode = IPv6
09:20:21 Fri Feb 10 2023        Notice (6)      DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.; 
09:20:28 Fri Feb 10 2023        Critical (3)        UCD invalid or channel unusable;

(edited)

Problem Solver

 • 

954 Messages

Hello @user_sa. I am sad to hear you are having issues with the modem and services. It has been a couple of days, are you still having issues, or were you able to get this resolved? 

I no longer work for Comcast.

Visitor

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6 Messages

@XfinityAaron - The issue with network connectivity is still very prominent. I have experienced three Xfinity network outages in the last two and a half hours.

update: Now 4 times in the last five hours.

(edited)

Problem Solver

 • 

770 Messages

@user_sa Thank you for letting us know. Since this is a known issue, and unfortunately with 3rd party equipment our hands are tied in regard to any firmware updates I would suggest swapping out the device for the time being, and then reverting back to the device when a "fix" is rolled out. I would also be happy to discuss shipping our gateway out, and possible discount on the rental to make sure it is not a service issue, or you can shop new devices here

 

I would like to check on the interruptions you mentioned, can you send me a direct message, so I can take a look? 

 

To send a "Direct Message":

Click "Sign In" if necessary

• Click the "Direct Message chat" icon

• Click the "New message" (pencil and paper) icon

• Type "Xfinity Support" in the "To:" line and select "Xfinity Support" from the drop-down list which appears. The "Xfinity Support" graphic replaces the "To:" line

• Type your message in the text area near the bottom of the window

• Press Enter to send it

I no longer work for Comcast.

Visitor

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9 Messages

2 years ago

For me, another tech came out a few days ago and found a fitting that they thought was suspicious. After replacing that we had the longest period of uninterrupted connection since I've been keeping detailed records. (Speed was 20Mbps higher than any prior but still way below advertised.) Motorola also was in contact and said there was an update that is meant to address frequent connection drops and requested that I reset (hold reset 30s while powered) the device.

Before reset we had and update of 3 days and 6 hours with:

   Hardware Version

V1.0

   Software Version

8611-21.3.7

   CM Certificate

Installed

   

Prod_21.3_d31

From the stats I grabbed at 3 days and 4 hours, OFDM PLC was showing 1,894,237,099 corrected errors and 1 uncorrected.

After reset the connection lasted 105 minutes before dropping. The software version is now rolled back to -19.2.18.

Contributor

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28 Messages

2 years ago

I understand if you get the replacement device under the warranty program the return of the original unit is at your expense.   The cost is likely not substantial, but reports that the replacement unit fixed the problem are few and far between.   I bought an Arris S33 after my 8611 problems.  The S33 is working flawlessly.   I'm hoping that whenever my S33 gives up the ghost down the road that the 8611 issues would be resolved and I may still yet get value from it.

Visitor

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44 Messages

@sigs​ Looks like others are having luck getting the Moto 8611 back to  normal operation within the last day.

Working software & consistent up time.

Looks like Comcast & Moto have been able to resolve it.

Too bad my S33 is now past its return window.

But at least I am future proof with a working 8611 in the closet.

Glad I never returned it!

(edited)

Frequent Visitor

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12 Messages

This is unbelievable! I had the S33 for about 6 months and kept having issues with it. I contacted Comcast via Twitter as that seems to be the best path to talk to someone who can do something and seems to be knowledgeable. I would schedule a tech to come out, only to get a recorded message the next day stating they found an issue and fixed it. Turns out their automated system was just resetting the modem! I wish I had known that, as the S33 was then past its return window. So, now I'm mad and I get them to send a tech out (they said they would waive charge, which they did). Tech said everything looks great! History on circuit/connection/whatever was also good. I ask him to look at Comcast forums and search for S33 and he says "Oh, I can see lots of other people are having issues" Duh! So, he calls supervisor, they talk a bit, and he has the nuts to suggest that I upgrade to Comcast Business - in my house! So, I say no thanks, and then he says to maybe try a different modem. So, I get the MB8611 - and more of the same [Edited: Language] The issue I was having with the S33 was it would work fine for a bit, then all of a sudden web pages would not load completely and I would have to refresh 2-3x to get it to come up completely. I get the MB8611 - and the same thing started to happen after about a week or so! Difference is, it went away on its own. So, I contacted Comcast on Twitter and they said that many people were having issues due to a firmware upgrade on the modem but it should be fixed, so fingers crossed! I will mention this (never had this happen before): When I had service initially installed, tech said I had a really hot signal! So, I am guessing that these modems can't deal with it and for some reason Comcast's own modems can. I did try to buy some attenuators and see if those would help, and they made it so it wouldn't work, but I found out later I was hooking them up in the wrong place/wrong direction.

It seems that if these are Comcast-approved modems, that they should take some responsibility to get them working! If they aren't going to bother, then stop allowing people to get their own equipment! Makes me want to start up my own ISP....

(edited)

Contributor

 • 

18 Messages

@GUS_GuyUsingSystem​ The issue is not resolved.  I contacted Comcast and Motorola about 10 days ago with the same issues everyone else is having with each blaming the other.  Motorola agreed to send a replacement MB8611 which arrived today and I started receiving drops within an hour or hooking it up.  For the past nine days I have been using a Netgear CM2000 which has worked perfectly.  I won't be buying any more Motorola products and I will use the two Motorola modems as bookends or door stops as that's about all they're good for.

(edited)

Visitor

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44 Messages

@milchuck​   Do you have the old software or new (faulty = new)

Contributor

 • 

34 Messages

2 years ago

Do not cave in to Motorola's greedy ways of making you pay for shipping. They will provide a return label if you pester them enough. I will let you know that it does not fix anything though.

Visitor

 • 

2 Messages

2 years ago

I'm another Xfinity user that is experiencing intermittent internet drops after upgrading to a Motorola MB8611. Xfinity came out 3 days ago and dropped new coaxial cable from the street to my house. Said their test showed it had 3 abrasions. The problem is still continuing so I'm going to see about getting a different modem. 

Problem Solver

 • 

892 Messages

Hi there @user_e5b5b5! Did the issue persist? 

I no longer work for Comcast.

Visitor

 • 

9 Messages

2 years ago

I have continued experimenting with my network since my last post. The biggest success I had was a period of 5.5 days without modem resetting itself. For the first 3 days I had modem connected directly to line without the cable boxes connected (and no splitter; just joiner). After 3 days I replaced the joiner with the unpowered splitter. I, of course, can't say why the reset happened in the end. I do know there were three resets in the next 6 hours. I checked the software version after the second reset and it had rolled back from -21.3.7 to -19.2.18.

I have now added back one of the cable boxes to see how things go.

Contributor

 • 

200 Messages

@user_jason​ based on your initial signal stats it looks like you have some sort of line problem.  That doesn't necessarily mean it's Comcast's problem, just that something is interfering with your signal around 670-700Mhz.  Given that it was working for the three days you had the modem running with no splitters it's possible the issue is with your household wiring.  You could also have a dodgy line from Comcast that works ok with no splitters.  It would be helpful if you could check your signal stats again with the modem in that no splitter configuration that worked for 3 days.  If that ugly mess around 670-700Mhz goes away you probably have a wiring issue in your house (sorry, your problem) and if it's still there (but probably less bad) it could well be a Comcast issue.

Expert

 • 

106.5K Messages

@user_jason 

Is there a cell phone tower near to your location ? Some LTE services operate in the upper part of that spectrum 670 to 700 MHz. You may be experiencing some spurious noise ingress / interference leaking into the line(s) somewhere from it. Good luck !

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? Please mark an Accepted Answer!tick

Visitor

 • 

9 Messages

(sidebar: is anyone else having trouble replying in forums? Last 5 days I haven't been able to post from my PC. I have been composing long replies on PC in OneNote and then pasting in from my phone. Unfortunately that seems to mean no well-formatted table, but I can post image of relevant channels. Anyway…)

I was coming back to give my update but now see the two above posts. Doesn't look like I'm getting notifications about activity now either.

So I captured connectivity stats regularly while I only had the cable modem as only device and no splitter - just joiner. At the after 3d 2h I had these stats shown at end of post. I think that would say Comcast issue per @zandor60657. They have been out and find no issue with their devices.
This of course those tests are done with my modem disconnected which means all other devices on my network are offline. This includes the T-mobile local cell box that is 1m from my cable modem. We don't have a strong cellular signal at our house so they gave us this box to cover the house. It does provide LTE. Perhaps @EG is onto something. I will now turn that off and see how we fare.

Visitor

 • 

9 Messages

Well, local cell box doesn’t seem to be it. I powered it down. Modem restarted 6h 15m after. Then 7 minutes after that. And another pair of restarts 4h 15m later. Here is snippet of the connection stats 3h after latest restart:

I guess next I'll try modem right where line comes in. 

Visitor

 • 

9 Messages

Initial results say there is no love for staying connected even if the troubles at higher frequencies are gone. Below will be some stats after 6h of connectivity right where line is in with an unpowered splitter to modem. (The two TV lines come out of the powered splitter behind the unpowered splitter.) The high freq errors appear gone or mitigated. (Assuming there is a problem in my house lines which those frequencies why don't techs see it with their scanners? Why does remote diagnostics (online chat) not see this as a problem? But also not as far as I know the source of the restarts.)

At 9h the modem restarted. I don't know how to get a lot of meaning out of the event log. Shouldn't there be an event that states why modem is restarting itself?

Maybe this restart is isolated. Will keep things as they are and see.

Snippet at 6h:

Visitor

 • 

3 Messages

2 years ago

I'm having similar issues.

I receive this error somewhat regularly from a new Motorola MB8611 cable modem:

    17:29:19
Mon Feb 20 2023
  Critical (3)   UCD invalid or channel unusable;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=xx:xx:xx:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1

The logs in the netgear router reflect the same:

[Internet connected] IP address: xx.xx.xx.xx, Monday, Feb 20,2023 17:29:51
[Internet disconnected] Monday, Feb 20,2023 17:29:50

I recently replaced my Arris G36 modem because it was unreliable, and now with a new modem and router, I am experiencing similar issues. 

An xfinity tech came out to the house before to inspect the lines, and they found a lot of noise on them. They cleaned that up, we also removed the amplifiers and splitters, so now there is only a single line from with a splitter at the end for the modem and cable box. 

Is there further troubleshooting that can be done to fix this? If this is happening with two different modems, I'm thinking that it might be the lines. Thank you

(edited)

Official Employee

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1K Messages

Hello @user_d5a98d Thanks for reaching out to our team for assistance with your connection concerns. Do you experience any issues with your connection if you bypass your router and just use your internet connection from your gateway? 

Does your modem come back online by itself? How long is your connection down when this happens? 

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Visitor

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3 Messages

I have not bypassed the router directly, but I have been looking at the modem logs and see that the modem loses connection a few times a day. It always comes back after 2-3 minutes, but that will disconnect the VPN, drop all the calls, stop any live streaming. I have been watching the modem logs regularly to see if there are any patterns or particular time of day, but I have not seen any. Last week I had solid uptime for three whole days, but the issue returned, and is back to dropping a few times a day. 

Expert

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106.5K Messages

2 years ago

@user_d5a98d 

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Frequent Visitor

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12 Messages

2 years ago

Ok, so for what it is worth, my web pages not loading issue was a misconfiguration in my home network. Now that I have that sorted out, my speed seems to be locked at 600M, not the 1.2G I'm supposed to be getting, so I have requested help in a different message. Also, I swapped my S33 back in and it is getting the same speed, so hopefully this is just a provisioning issue on Comcast's side. 

Visitor

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2 Messages

2 years ago

Update from my post a month ago:  My problem with intermittent internet loss with my Motorola MB8611 Modem has magically disappeared. I had received an Arris Surfboard S33 from Amazon, but I never installed it because my internet became more stable. My only guess is that Motorola finally sent a corrective firmware out. I guess I'll never know for sure, but I'm glad it has been resolved. Returning my unopened Arris modem to Amazon.      

Contributor

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200 Messages

@user_e5b5b5​ 

Yeah, you'll probably never know.  Could be a modem firmware update, could be Comcast fixed something, could be something else.  But hey, at least it's working!  

Visitor

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44 Messages

@user_e5b5b5​   What is your current Firmware version # on the Moto 8611?

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Official Employee

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1.2K Messages

I am very glad to hear your internet is stable now. If you do run into any issue with your service feel free to reach out to our team here.

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

Visitor

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4 Messages

2 years ago

I am experiencing the same as everyone else. Have had the 8611 for a year with no issues until recently. Had good luck with Surfboard in the past. May try that route, but will check with Comcast and Motorola first. People have mentioned their warranty, but it's not clear what it is. Will look for that next. So frustrating!

Visitor

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4 Messages

@swilson317a​ Ha! Here is a quote from the NY Times! "The Motorola MB8611 is our pick if you already have gigabit or faster internet services: It's one of the least expensive DOCSIS 3.1 gigabit modems with a 2.5GbE port, it has a two-year warranty, and it's well designed." 

Visitor

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4 Messages

Thought I'd report back here. For some reason, Comcast still had my old modem listed on my account. Maybe I forgot to work with them to switch it. I worked with a support agent. Once I gave her the mac address of the old modem and the new one, she updated the modems on my account. I then rebooted again. When I re-checked the speed test (speakeasy.net, not Comcast's test, as Comcast doesn't include upload speed), I noticed my upload speed doubled. YAY! Am hoping this will address my issues with the internet dropping randomly. Good luck to those still having issues!

Contributor

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19 Messages

1 year ago

I purchased a new Motorola MB8600 three days ago after my Arris 6141 experienced weeks of intermittent connectivity. The second tech came out and recommended that I replace my 2020 Arris 6141 as he didn't see any other problems on the Comcast side.  I've had three Xfinity techs come out to explore the issue, and the third one scratched his head this morning (6/18/23) and said, "In my ten years of working at Xfinity, I've never seen this issue and am completely stumped." They have put in a Xfinity modem/router to see if I continue to have issues. I really don't want one, but I agreed to try it out free for 30 days.

So I've had two different brands of my own modem do exactly the same thing. Time out, then re-up and work again. Sometimes for 24 hours, sometimes for 2, sometimes for just 15 minutes. All over the last month. Very random. From what I'm reading, I need to reconnect the modems I now own and download the history from Arris and Motorola. If there seems to be an issue, then call (sigh) each of these companies to try and figure out what is wrong and replace at least one of them...or go to an Arris SB33, which someone bought and installed and then had no issues whatsoever.

But I also read that it might be a noise filter that XFINITY installed without my knowledge. How do I find out if they did that? Because if they did and I can remove it, this might save me HOURS of trying to decipher what is wrong with the cable modems themselves. 

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