Visitor

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3 Messages

Tuesday, September 30th, 2025

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Constant Drops in Service - Repeated "Time Not Established" Errors

This is yet another post for the constant drops in internet service related to the "Time Not Established" error that is repeated over and over again in the Event Log for the Motorola MB8611 modem.   I have researched this issue in this forum and have discovered many others with the same issue - and it has been happening for a while.  Here are just a few examples:

https://forums.xfinity.com/conversations/your-home-network/time-not-established-critical-3-no-ranging-response-received-t3-timeout

https://forums.xfinity.com/conversations/your-home-network/motorola-mb8611-rebootsrestarts-multiple-times-a-day-please-help

https://forums.xfinity.com/conversations/your-home-network/mb8611-t3-timeouts-and-timing-synchronization-failures-lead-to-frequent-disconnects

I first noticed my internet dropping out a couple of weeks ago and figured it was just my WiFi/mesh network needing a reboot.  However, after several rounds of rebooting both the router and the modem, the issue persisted.  I reverted back to factory defaults on both the router and modem and the issue still remains.  Finally did a little Googling around on the issue and found that I am not alone.  

The modem never fully “reboots”.  Internet drops out for about 2-3 minutes then comes back up.  You would never know unless it happens during a Teams call or while online browsing, etc.  Status LED's on modem never indicate a problem.  Yes, all cables and connections are tight and secure.  What makes me believe this is NOT a hardware issue is not only the multiple reversions back to factory defaults, but also the multiple other posts with this exact same issue.  Not to mention the fact that I have had ZERO issues up until I first noticed the issue emerging a couple of weeks ago.  What's ever worse is that we ditched AT&T's fiber internet service for Xfinity earlier this year which has proven to be a mistake.  

Why the extended period of time without any drops in service or any issues at all?  Why the sudden appearance of this issue?  Nothing changed.  

I have yet to find a solution to this problem - all of the threads just drop off.  

Motorola MB8611, Software Version 8611-19.2.18

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Official Solution

Visitor

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3 Messages

7 days ago

Update on this issue:

If anyone else is experiencing this issue, I can confirm that it is more than likely related to your modem.  I was using the Motorola MB8611, then switched to the Arris S34 modem.  I checked Xfinity's list of approved devices and of course, the MB8611 was no longer listed.  Go figure.  

Zero issues after switching to the Arris, which is great but I really wasn't excited to spend $200 on another modem - especially since the MB8611 was only out of the box for a few months.  

I might try to contact Motorola to see if there is anything that I can do as the user - as far as a software update or something, but not a ton of options within the user interface to do or change anything.  

Official Employee

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1.6K Messages

We do appreciate you sharing the update with us on the different modem @user_ytukgh! I am happy your signal has been more stable since the switch. Please let us know if you have any other questions/concerns, we are happy to help! 

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Official Employee

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2.4K Messages

12 days ago

 

user_ytukgh Welcome to our community forum! You've reached the perfect place to get help with your Xfinity internet stability. We will troubleshoot with you until you confirm everything is running smoothly. 
Please send a direct message by clicking the chat icon in the upper right corner of the page, click on the pen and paper icon, then enter “Xfinity Support” in the “To” section. Include your name and address so I can find the account and get started on a resolution. 

 

Visitor

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3 Messages

@XfinityEmilyB​ , DM sent.  

Expert

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113.9K Messages

12 days ago

@user_ytukgh @XfinityEmilyB 

Please circle back here and post any possible solutions for the issue here in these open public forums so that all readers here may benefit from the exchange / info. This is in keeping with the spirit for which these public help forums were originally intended. Thank you.

Expert

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113.9K Messages

7 days ago

@user_ytukgh 

The S34 is just a plain vanilla cable modem (no built-in WiFi router component) so there's not much to the user interface. And the ISP is responsible for updating the firmware through the cable system. An end user can't update it. Good luck with it !

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