TH

Saturday, September 7th, 2024 2:21 AM

Intermittent Sync Loss/Connection Drop

For the past couple weeks, I've been seeing intermittent losses in connection for anywhere between a couple seconds and a couple minutes. The frequency seems to vary; it may be fine for a few hours, but other times it drops 3 times within 20 minutes. I haven't had any issues for years before this.

I've restarted/power cycled my modem many times, and have even replaced it entirely last week (with no improvements).

Originally, I was using a Motorola MB7621 and tried switching to an Arris SB8200.

This is the info from the Arris modem

Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
20 Locked 256QAM 495000000 Hz 2 dBmV 40 dB 0 0
4 Locked 256QAM 399000000 Hz 2 dBmV 40 dB 0 0
12 Locked 256QAM 447000000 Hz 2 dBmV 40 dB 0 0
28 Locked 256QAM 543000000 Hz 1 dBmV 40 dB 0 0
1 Locked 256QAM 381000000 Hz 2 dBmV 40 dB 0 0
2 Locked 256QAM 387000000 Hz 2 dBmV 40 dB 0 0
3 Locked 256QAM 393000000 Hz 2 dBmV 40 dB 0 0
5 Locked 256QAM 405000000 Hz 2 dBmV 40 dB 0 0
6 Locked 256QAM 411000000 Hz 2 dBmV 40 dB 0 0
7 Locked 256QAM 417000000 Hz 2 dBmV 40 dB 0 0
8 Locked 256QAM 423000000 Hz 2 dBmV 40 dB 0 0
9 Locked 256QAM 429000000 Hz 2 dBmV 40 dB 0 0
10 Locked 256QAM 435000000 Hz 2 dBmV 40 dB 0 0
11 Locked 256QAM 441000000 Hz 2 dBmV 40 dB 0 0
13 Locked 256QAM 453000000 Hz 2 dBmV 40 dB 0 0
14 Locked 256QAM 459000000 Hz 2 dBmV 40 dB 0 0
15 Locked 256QAM 465000000 Hz 2 dBmV 40 dB 0 0
16 Locked 256QAM 471000000 Hz 2 dBmV 40 dB 0 0
17 Locked 256QAM 477000000 Hz 2 dBmV 40 dB 0 0
18 Locked 256QAM 483000000 Hz 2 dBmV 40 dB 0 0
19 Locked 256QAM 489000000 Hz 2 dBmV 40 dB 0 0
21 Locked 256QAM 501000000 Hz 2 dBmV 40 dB 0 0
22 Locked 256QAM 507000000 Hz 2 dBmV 40 dB 0 0
23 Locked 256QAM 513000000 Hz 2 dBmV 40 dB 0 0
24 Locked 256QAM 519000000 Hz 2 dBmV 40 dB 0 0
25 Locked 256QAM 525000000 Hz 2 dBmV 40 dB 0 0
26 Locked 256QAM 531000000 Hz 2 dBmV 40 dB 0 0
27 Locked 256QAM 537000000 Hz 1 dBmV 40 dB 0 0
29 Locked 256QAM 549000000 Hz 1 dBmV 40 dB 0 0
30 Locked 256QAM 555000000 Hz 1 dBmV 40 dB 0 0
31 Locked 256QAM 561000000 Hz 1 dBmV 40 dB 0 0
32 Locked 256QAM 567000000 Hz 1 dBmV 40 dB 0 0
194 Locked OFDM PLC 957000000 Hz -2 dBmV 39 dB 1386014 0
193 Locked OFDM PLC 722000000 Hz 0 dBmV 42 dB 1532669 0

Channel ID Lock Status US Channel Type Frequency Width Power
20 Locked SC-QAM 35600000 Hz 6400000 43.0 dBmV
17 Locked SC-QAM 16400000 Hz 6400000 40.0 dBmV
19 Locked SC-QAM 29200000 Hz 6400000 42.0 dBmV
18 Locked SC-QAM 22800000 Hz 6400000 41.0 dBmV

Event Log:

06/09/2024 18:05:01
notice
REGISTRATION COMPLETE - Waiting for Operational status;CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:58
warning
RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:55
critical
Config File Rejected due to Invalid or Unexpected TLV 11;CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:55
notice
TLV-11 - unrecognized OID;CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:54
warning
MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=XX:XX:XX:XX:XXCMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:54
notice
CMSTATUS:DS_Diplexer_Mode_Change_Ignored:[TLV-84.3], [1002MHZ];CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:54
notice
CMSTATUS:DS_Diplexer_Mode_Change_Ignored:[TLV-84.2], [108MHZ];CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:54
notice
CMSTATUS:US_Diplexer_Mode_Change:[TLV-84.1], [5-42MHZ];CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:39
notice
CMSTATUS:DS_Diplexer_Mode_Change_Ignored:[TLV-21.3], [1002MHZ];CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:39
notice
CMSTATUS:DS_Diplexer_Mode_Change_Ignored:[TLV-21.2], [258MHZ];CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:39
notice
CMSTATUS:US_Diplexer_Mode_Change:[TLV-21.1], [5-85MHZ];CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:39
notice
CMSTATUS:US_Diplexer_Mode_Change:[TLV-9], [5-85MHZ];CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:39
notice
Honoring MDD; IP provisioning mode = IPv6;CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:31
critical
Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:04:02
notice
CM-STATUS message sent. Event Type Code: 5; Chan ID: 20; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:03:52
notice
MDD Recovery following MDD Loss;CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:03:47
warning
Lost MDD Timeout;CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:03:46
notice
MDD Recovery following MDD Loss;CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:03:44
warning
Lost MDD Timeout;CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:03:40
notice
CM-STATUS message sent. Event Type Code: 2; Chan ID: 15; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;
06/09/2024 18:03:33
critical
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=XX:XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.1;

The Motorola modem further indicated some FEC framing and QAM/QSPK timing issues on the "SYNC Timing" errors, but I don't have logs at the moment

1 Message

3 months ago

Same issue here around Bay Area. Since the past several days, internet would go out for several seconds and back and out. It's so annoying.

Official Employee

 • 

1.7K Messages

@user_fedlke Welcome to our community forum! I rely on my internet every day so I'd be reaching out if I was having intermittent issues. We're a team of experts dedicated to addressing all your questions and concerns and we'll work alongside you to advocate for the best possible resolution :). What troubleshooting steps have you tried so far? Do you see any documented issues in the area on our Status Page?

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

Official Employee

 • 

1.7K Messages

3 months ago

Good evening @Tony.H, and thank you for reaching out on our Community Forums regarding your connection issues, we appreciate it! I hope you are otherwise having a wonderful weekend and we are sorry to hear that you have been experiencing intermittent losses in connection for the past couple of weeks. We appreciate the details provided and letting us know that it lasts anywhere between a couple second and couple minutes as well as letting us know that you have already tried restarting/power cycling your modem and even tried replacing it. 

 

We'd be happy to run some diagnostics and check some things on our end to see how your network health is to help determine next best steps to getting this resolved. If needed, we'll schedule one of our expert technicians to investigate further. Rest assured, our team is on your side and here to help how we can. 

 

To get started, we will need to collect a few pieces of information to locate the account. Can you please send us a Direct Message with your first and last name along with the service address on the account?

To send a "Direct Message" ("Private") 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

We look forward to working with you further. 

 

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