Change codec on INVITEs after REFER
Hello,
I have a call flow that is originally setup as g711 and after it's transferred (REFER) the INVITEs need to advertise g729 as the primary codec.
Call Flow
Leg 1 = Agent makes an outbound call with EO INVITE with g711 (preference), g729. Carrier responds with g711
Agent -> SBC -> Carrier -> Customer
Leg 2 = Agent hangs up and the customer is transferred via REFER to a survey vendor. The survey only accepts g729. The call is now between the customer (via the carrier) and the survey company. Two INVITEs are sent out after the REFER to setup the call. One to the carrier and the other to the survey company.