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SLOW speeds... 2 frequent log critical errors:No Ranging Response & SYNC failure

New Poster

SLOW speeds... 2 frequent log critical errors:No Ranging Response & SYNC failure

I just had a Comcast tech out and he said the lines are perfect from the pedistal all the way to my modem. He said they are actually too strong and installed an attenuator.

 

But, just like it has been for the last month, after being at 60mbit DL fr abotu 12 to 24 hours, i drops to between 4-9mbit DL speeds.

 

here's the errors I'm seeing in the log and the signal screenshot attached.

 

Frequent Critical Log errors...

No Ranging Response received - T3 time-out
SYNC Timing Synchronization failure - Loss of Sync

 

 

thx for the help!

 

Comcast_SIGNAL.JPG
Expert

Re: SLOW speeds... 2 frequent log critical errors:No Ranging Response & SYNC failure

What model modem do you have? Are you testing speeds directly connected to the modem (no router)?



"Keepin' it clean since '09"
I am not a Comcast employee, just a moderator.
New Poster

Re: SLOW speeds... 2 frequent log critical errors:No Ranging Response & SYNC failure

Motorola SB6120

 

What are these errors... seems like CRITICAL errors are likely causing my problem.

 

This issue is NOT computer or network related. Either the modem is going bad or the comcast signal is the problem.

 

This problem just started a bit over a month ago and speeds are fine for 12 to 24 hours after a modem reset to get the speed back to what it should be.

 

Does anyone know what could cause these critical errors?  thx for the help

Expert

Re: SLOW speeds... 2 frequent log critical errors:No Ranging Response & SYNC failure

Critical errors are okay as long as you are only seeing them once in a while. If you are seeing multiple T3 and T4 errors in a 24 hour period it is an indication of an issue. These errors just mean the modem lost communication with Comcast briefly. It does not really tell us why. With that said, I'd strongly recommend that you upgrade your modem, the non-retail version of that device is already End of Life and the retail version won't be supported much longer either. Check out https://mydeviceinfo.xfinity.com for compatible modems.



"Keepin' it clean since '09"
I am not a Comcast employee, just a moderator.