Hi
I am experiencing intermittent one-way audio problems and could really use some help!.
We are using CUCM 10.5.1 with a SIP trunk to an external SIP provider. Internal calls are bi-directional and working fine.
'MTP is required' is checked on SIP trunk.
The one-way audio is not always happening, its intermittent. During normal working calls via the external SIP Provider, all RTP packets are being sent from IP phone to CUCM, which forwards it to the SIP provider.
When we have one-way audio issues, the RTP media packets are being sent directly to the SIP provider from the IP Phone. There is no network access from IP phone to SIP provider which will be why we only have one-way audio.
Network access should not be the cause because audio should be going via CUCM and not direct from IP phone to external SIP provider.
Any advice will be appreciated! Many thanks!
Cheers, Mark
