Having an interesting issue with an IP Trunk pilot,
Users are being disconnected when certain tones are heard on a call. We can recreate this problem anytime by playing the Blackberry default ringer while a call is in progress. According to the carrier they are set up for mid-call codec renegotiation when fax tone is heard on a call. The CUCM rejects the codec renegotiation and the carrier disconnects.
TAC provided an option for the CUBE which is supposed to pass the codec renegotiation rejection message from Call Manager to the SBC but this has had no effect on resolving the problem.
voice service voip
This error response applies to the following
4xx - request failure responses
5xx - server failure responses
6xx - global failure responses
This command should pass the error received along both call legs.
While this could be useful feature at times I was wondering if anyone else has run into this and has a fix.
I have this problem too.