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user_cae28c
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2 Messages

Tuesday, June 6th, 2023 6:18 AM

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Motorola 8611 frequent connection drops

Hi, I am having what seems to be a common issue. I have exactly the same symptoms as an earlier post https://forums.xfinity.com/conversations/your-home-network/motorola-mb8611-modem-frequently-loses-connection-to-xfinityreboots/63293b7c2ff2c66589fffdb7 . My connection drops several times per day, sometimes multiple times per hour. However there doesn't seem to be a common solution available (or at least it didn't seem to get posted). Could someone help me resolve this issue?

Event Log  
  
    Time    Priority    Description 
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    23:00:41
Sun Jun 4 2023		   Critical (3)   UCD invalid or channel unusable;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    01:42:13
Mon Jun 5 2023		   Critical (3)   UCD invalid or channel unusable;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    03:01:01
Mon Jun 5 2023		   Critical (3)   UCD invalid or channel unusable;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
    05:28:34
Mon Jun 5 2023		   Critical (3)   REG RSP not received;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    05:28:43
Mon Jun 5 2023		   Critical (3)   UCD invalid or channel unusable;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    07:23:28
Mon Jun 5 2023		   Critical (3)   UCD invalid or channel unusable;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
    08:23:08
Mon Jun 5 2023		   Critical (3)   UCD invalid or channel unusable;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    11:28:02
Mon Jun 5 2023		   Critical (3)   UCD invalid or channel unusable;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Critical (3)   Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    Time Not Established   Notice (6)   Honoring MDD; IP provisioning mode = IPv6
    11:57:17
Mon Jun 5 2023		   Notice (6)   DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    11:57:25
Mon Jun 5 2023		   Critical (3)   UCD invalid or channel unusable;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
    17:48:35
Mon Jun 5 2023		   Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"]CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;

Question

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Updated 

2 years ago

 • Edited

71

2

0

CCEdgardo

Problem Solver

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513 Messages

2 years ago

Hi there, @user_cae28c. Thank you for reaching out to us via our forums. We appreciate you taking the time to reach out and post your issues with the results. From what we are showing by other customer resolutions in the forums, the main culprit may be the modem itself. We are showing customers changing from their modem to a different one and not having any other issues. However, if you would like us to troubleshoot the issue and verify if we see any abnormalities with the signal, please send us a private message to assist you. 

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user_cae28c

Visitor

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2 Messages

@XfinityEdgardo​ I installed a new modem earlier this week, and it ran for one day before crashing and restarting. The logs include the same timing issue as before. It may not be limited to the hardware.

31/12/1969
16:00:22		 3 CMSTATUS:DS_Diplexer_Mode_Change_Ignored:TLV-21.2, 258MHz.
31/12/1969
16:00:22		 3 CMSTATUS:DS_Diplexer_Mode_Change_Ignored:TLV-21.3, 1002MHz.
31/12/1969
16:00:23		 3 CMSTATUS:US_Diplexer_Mode_Change:TLV-21.1, 5-85MHz.
31/12/1969
16:00:37		 3 CMSTATUS:DS_Diplexer_Mode_Change_Ignored:TLV-84.2, 108MHz.
31/12/1969
16:00:37		 3 CMSTATUS:DS_Diplexer_Mode_Change_Ignored:TLV-84.3, 1002MHz.
13/6/2023
08:50:02		 3 CMSTATUS:US_Diplexer_Mode_Change:TLV-84.1, 5-42MHz.
13/6/2023
08:50:16		 3 UCD invalid or channel unusable;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;
31/12/1969
16:00:15		 3 CMSTATUS:US_Diplexer_Mode_Change:Init, 5-42MHz.
31/12/1969
16:00:19		 3 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

(edited)

2 years ago

0

EG

Expert

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110.3K Messages

2 years ago

@user_cae28c 

Here's how to send that requested private message / 'direct message';

Click "Sign In" if necessary.
 
Click the "Direct Message" icon  in the upper right corner or https://forums.xfinity.com/direct-messaging  
 
Click the "New message" (pencil and paper) icon.
 
The "To:" line prompts you to "Type the name of a person". Instead, type "Xfinity Support" there.
 
As you are typing a drop-down list appears. Select "Xfinity Support" from that list.
 
An "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.


See https://comca.st/3KQF8q9 for an example.

[Permission from and credit given to BruceW].

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