thanks for your answer, i needed a long time to belive this. But i found a way to let my app running with endless background execution time using the expiration handler and receive the sip over udp invite myself, hope app store accept this workaround.. now my last problem is starting sound from bg. In fg works well using the pjsua api but not in bg i set the info.plist entry have i to do something else to get sound working? greetings, matthias