We have two incoming dial-peers pointing to two subscribers on a cisco SIP cube.
Calls hitting first dial-peer does not have any issue. For calls hitting the other dial-peer pointing to secondary subscriber, called party hears ring-back even after call is answered on jabber for incoming PSTN calls.
Looks like an issue with SDP negotiation between cube and subscriber. In the attached image, First call is successful where as the second one is having the issue. Middle line - Cube, Last two lines are subscribers