Forum Discussion

StephenEM's avatar
StephenEM
Joining in
2 years ago

SYNC Timing Synchronization failure / RCS Partial Service

Hi - seeing others post about it here, I've got regular timing sync problems, started in the last month and now a (more than) daily occurrence.  I did have an engineer booked this week, but was told 'there's a problem in the area so your engineer is cancelled' - so adding here for a record at least.  Would welcome any help and glad to share any more info.

Here's today's BQM graph  (only been running for a day or so after seeing the forum) :

 

And some network logs (since midnight).  I have events like this recorded since 30 December.

22/01/2024 14:31:13

Warning!

RCS Partial Service;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 14:15:32

Warning!

Lost MDD Timeout;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 14:15:27

Warning!

RCS Partial Service;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 14:15:27

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 14:15:27

Warning!

RCS Partial Service;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 14:15:27

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 14:15:25

Warning!

RCS Partial Service;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 14:15:25

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 14:15:23

Warning!

RCS Partial Service;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 14:15:23

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 14:15:22

Warning!

RCS Partial Service;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 14:14:14

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 09:47:52

Warning!

RCS Partial Service;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 09:15:29

critical

No Ranging Response received - T3 time-out;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 09:11:53

critical

Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 09:10:7

Warning!

Lost MDD Timeout;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 09:10:2

Warning!

RCS Partial Service;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 09:10:2

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 09:10:2

Warning!

RCS Partial Service;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 09:10:2

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 06:22:53

Warning!

RCS Partial Service;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

22/01/2024 01:23:23

critical

No Ranging Response received - T3 time-out;CM-MAC=*:*:*:*:*:*;CMTS-MAC=*:*:*:*:*:*;CM-QOS=1.1;CM-VER=3.0;

 

 

 

 

4 Replies

  • jbrennand's avatar
    jbrennand
    Very Insightful Person

    For latest info, call the “free & automated” Service Status number - 0800 561 0061 - which usually gives the most up to date info. and tells you of more local issues and fix estimates, down to street cab/ postcode level.

  • Reece_MH's avatar
    Reece_MH
    Forum Team (Retired)

    Hi StephenEM 👋

    Thanks for posting, and a warm welcome to the Forums.

    I'm sorry to hear you're experiencing some issues with your service. I've taken a look at things on our side, and I can see that you have booked a Technician to come and look into this.

    Please do let us know how this goes, and we'll be happy to assist further, if needed.

    Cheers,

  • Same with my log as of today (though been like it since last week or so).

    Had external tech team on site yesterday solving a local street broadband dropouts issue. Even though my Wifi connection is somewhat okay after the so called “fix”, I noticed in the hub (3ac) router status that the UPSTREAM is using a modulation of 32 QAM on one of the channels. Now every so often I am seeing RCS Partial Service in the Network Log and Sync Timeouts. Also seem to be getting lots of POST RS errors which I am unsure about.

    Here’s my current log:
    UPSTREAM:

    12360000042.5512032 qam10
    23660000043.8512064 qam7
    34310000044.5512064 qam6
    44960000045512064 qam5
    53010011643512064 qam8



    Upstream bonded channels

    ChannelChannel TypeT1 TimeoutsT2 TimeoutsT3 TimeoutsT4 Timeouts
    1ATDMA0000
    2ATDMA0000
    3ATDMA0000
    4ATDMA0000
    5ATDMA0000

    DOWNSTREAM RS:

    ChannelLocked StatusRxMER (dB)Pre RS ErrorsPost RS Errors
    1Locked37.643330
    2Locked37.363312
    3Locked37.355180
    4Locked37.668226
    5Locked38.62217
    6Locked37.653156
    7Locked37.642281
    8Locked37.359108
    9Locked37.632132
    10Locked38.67035
    11Locked37.62821
    12Locked37.365171
    13Locked37.691245
    14Locked37.644146
    15Locked37.638173
    16Locked37.665156
    17Locked37.348108
    18Locked37.675187
    19Locked37.689318
    20Locked37.648146
    21Locked37.651186
    22Locked37.688204
    23Locked37.662133
    24Locked37.373175
    14/08/2025 20:08:55Warning!RCS Partial Service;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 15:07:54noticeLAN login Success;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 14:12:33Warning!RCS Partial Service;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 14:12:22criticalNo Ranging Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 14:11:58criticalUnicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 14:11:58criticalRanging Request Retries exhausted;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 14:01:37criticalNo Ranging Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 14:01:37Warning!RCS Partial Service;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 14:01:28criticalNo Ranging Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 13:58:46Warning!RCS Partial Service;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 13:58:40criticalUnicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 13:58:40criticalRanging Request Retries exhausted;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 13:57:56criticalNo Ranging Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 09:29:10noticeLAN login Success;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    01/01/1970 00:01:41criticalNo Ranging Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 08:47:28noticeLAN login Success;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    01/01/1970 00:02:3criticalNo Ranging Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 07:58:1noticeLAN login Success;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 07:54:30Warning!RCS Partial Service;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
    14/08/2025 07:35:49criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=;CMTS-

    Anyone with ideas please as to the overall issue. Have tried the suggested “Hard Reset” by VM CS

     

     

     

    • Kath_P's avatar
      Kath_P
      Icon for Forum Team rankForum Team

      Hi hamtrektng, 

      Thanks for coming back here. 

      I can see we've already replied to your own thread here: Still says intermittent signal despite tech visit

      Please make sure you are only posting once about your issue. If you need to update the thread then just reply to your original thread rather than posting on an older one. We understand it's frustrating when something's not right however posting more than once about the same fault makes the boards look busier than what they actually are. It also means we could take longer to reply due to needing to sift through duplicate posts.

      Have a look at the reply on the other thread and stick with that one so we keep all the information in one place. 

      Thanks,