Hi team,
it's been almost 4 months since I've had a SIP service paraded by mismatch codec issues. It's a TRUNK SIP from embratel operator, they use a Hauwei SBC on their side. I have an ISR29XX voice gateway with 128 PVDM. The carrier asked to change the codec negotiation to G729 because it was under contract the Band for 30 simultaneous calls in G729. We did that and we noticed that some calls were dropping. When checking using debug sip messages, we saw that the carrier was forwarding a re-invite with codec change to G711 and automatically our gateway informed that it did not have this codec in its list. The operator sent the bye reason code 488, and the call fell.
Flow:
PSTN EBT -->SIP TRUNK --> GW-ISR2921 -->SIP TRUNK CUCM --> CUCM --> CTI --> UCCX -->IVR -->CSQ
When we configure the two codec preference in the Gateway for some reason the callmanager prioritizes the G711. But in some moments of testing I saw the different behavior that did not reapply. The codec always closing at g729, always picking up the first preference.
The PSTN open a case to hauwei.
Does anybody knows samething like that ?
