Hi Klaus, Klaus Darilion wrote: > There was no firewall or ALG active - I suspect a bug in pjsip that it > closed the port before getting the resonse -> thus ICMP error. > Did check your pcap again and some messages are missing, specially ALL traces where the RTP port 6666 is used. The "Destination Unreachable" message is NOT a bug. PJNATH, by the way the hottest OSS NAT traversal library out there, after the successful NAT discovery just shutdown the used socket since it's no more needed. Cheers, Alain -- | \ | / _\/_ .-'-. //o\ _\/_ -- / \ -- | /o\\ ^~^~^~~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~~^^~~^~^|~^~~~|^~^^` ^~^~^~~^~^~^~^~^~^~^~^~^~^^~^~^~~^~^~^~^~^~^~^^- | 1024D/A9F85A52 2000-01-18 Alain Totouom <totouom at gmx.de> PGP FingerPrint DA180DF2 FBD25F67 0656452D E3A27531 A9F85A52