I'am facing problem regarding outgoing calls via SIP trunk from CUCM to external IVR. I put SIP trunk in region B. When I put telephone in region B everything is ok with g711 codec. Problem is when I put telephone in region A. Region A relationship with Region B is set to g711. In such case call fails. I used sniffer to look into SIP session beetwen CUCM and IVR and it looks like this:
CUCM -> IVR Invite with SDP offering g711
IVR -> CUCM Trying
IVR -> CUCM OK with SDP offering g711
CUCM -> IVR ACK
CUCM -> IVR Bye with cause 47
IVR -> CUCM OK (cute )
As I can see 47 indicates a "resource unavailable" event. Any clues about that. it is g711 to g711 so there's no need to transcode.