[VoiceOps] Adtran TA900 timing problems

Paul Timmins paul at timmins.net
Mon Nov 4 12:18:47 EST 2013

We've never seen that here. Do you see incrementing errors on either side of the interface? Do you have log entries on the TA900s?

I assume you tested newer (or older) firmware revisions on the TA900s?

On Mon, 11/04/2013 11:24 AM, "My List Account" <mylists at battleop.com> wrote:

Has anyone ever seen this problem?  I have a good number of TA900s and TA900Es on the other side of a 7206VXR with PA-MC-T3 cards.   Once every few months SIP accounts in the TA900s that are attached to FXS ports have trouble passing audio.  It sounds like the audio stream is On/Off about every 3 seconds.   The only “fix” is to change the timing from the T1 to internal or reboot the router which effectively does the same thing.
It never has an effect on PRI/T1 voice, Hosted PBX behind that router, or data traffic behind the router.  We never see a problem with other Cisco routers connected to the same DS3(s) including voice on Cisco 2431-8FXS and 16FXS rotuers.   When the problem happens it will happen to every TA900 or TA900E at the same time on the same DS3.   It’s always a single random DS3 in the same box.
I’ve had countless tickets open with our DS3/T1 Provider over the years and they always say they see nothing.  Adtran’s only solution so far is to change the timing when it happens.   One tech suggested we just run internal timing all the time but that seems to only work for 31 days.  I’ve completely swapped out the 7200 and the PA-MC-T3 cards.   I’ve had a JDSU test set on random DS3s for weeks at a time and never seen a problem.
We set up the routers so that the T1 is the Primary and the Internal is secondary.  I suspect that something happens to the primary clock and it fails to the internal clock.   When the primary clock becomes available again the TA900 does not revert back to the T1 clock.  So when we get to around 31 days the internal timing fails and then the problem with the audio happens.  

> VoiceOps mailing list
> VoiceOps at voiceops.org
> https://puck.nether.net/mailman/listinfo/voiceops
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://puck.nether.net/pipermail/voiceops/attachments/20131104/f2a6f9db/attachment.html>

More information about the VoiceOps mailing list