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SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing

Joining in

For the last few weeks I've noticed my router periodically turning itself off. When looking at the router network log, I see this:

25-06-2024 09:31:04criticalSYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XXXXXXXXXXXXXX
25-06-2024 09:31:03criticalCable Modem Reboot because of - HW or Power-On Reset

Alongside this the speeds I get are around 400meg below what I should be getting. Very frustrating on a service I pay very good money for.


Very Insightful Person
Very Insightful Person

Check with Area faults on 0800 561 0061 If you have a VM landline 150 this goes down to post code level. You could also try the web page status, but this is not recommended as it only covers issues that affect a very large number of customers.

VM will not dispatch any technicians while an area fault exists.

If no area faults found:

The primary place to report faults or for service requests is Customer Services on 0345 454 1111/150 if you have a VM landline or wait two or three days for a VM staff member to get to your post. This board is not a fault reporting system.

There are 10 types of people: those who understand binary and those who don't and F people out of 10 who do not understand hexadecimal c1a2a285948293859940d9a49385a2

Forum Team
Forum Team

Hello willsetten


Sorry to hear of the Hub issues experienced. We appreciate you taking the time to raise this via the forums, welcome to the community.


From checking the connection and equipment, there does appear to be some issues that will require a visit. I will send you a Private Message to get some more details from you to assist. Check the envelope in the top right of the forum when signed in for the message.