I have a lot of problems getting my SIP provider connections to work. I am using 3 separate SIP providers (for different destinations/services), and sometimes things work and sometimes they don't. Registrations work OK, but often there is no audio, or the call establishment fails. Makes me suspect a network/NAT issue. Something that I do worry about is the log messages saying "sofia.c:995 nua_i_outbound: unknown event 8: 101 NAT detected". Julf