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WAN based voice-call issues after 4520 MCU upgraded to v4.5

I upgraded out MCU last week and performed ( what I thought was ) sufficient testing including TMS scheduled conferences, ad-hoc conferences, video only, voice only calls. etc.. One thing I didn't test was inbound calls from field offices using the short dial (OnNet) to the bridge, whoops.  I began getting emails from frustrated users in the middle of the night saying this was broken. 

We're running Cisco call manager 8.5.

The users who dialed the full 10 digit pstn number got through fine but folks using on-net dialing got "unable to complete the call" messages.


The system log on the MCU shows the following entries for the failed calls including "Unable to establish call due to lack of matching media codecs"

My call manager guru says he believes it to be a transcoding issue g711/g729.  All of the audio/video codecs to and from the MCU are enabled however.

I was able to roll back the upgrade to 4.4 and we're back up and running.


I thought I would throw this out to the community to see if anyone has any ideas before I open a TAC case




VIP Super Bronze

Can you share the SIP dialog

Can you share the SIP dialog between CUCM and the MCU? INVITE, 100, 180/183, 200 OK, ACK?

CUCM can do the packet capture directly from the CLI as long as you run it from whatever node the SIP trunk is being sourced from (primary of that trunk's CMG).

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