Hello, I'm troubloshooting an issue where there is no ringback for incoming calls. The callflow is:
PSTN -->(SIP)--> CUBE --> IVR --> (Enter extension XXXX) ---> CUCM ---> (Extension XXXX)
While the extension is ringing there is no ringback for the caller. A 180 ringging is sent to the pstn when the IVR takes the call, and when the call is sent to the extension the CUCM sends a 180 to the CUBE but it is not retransmited to the PSTN (I supposse because it already received one before, right?). Instead, a Re-Invite with SDP is sent to the caller. Is that correct? In any case, ringback is not playing. I can attach the call diagram:
Thank you.