[Freeswitch-users] I've been bored about no Audio(NAT, Firewall or ...)!

I can not detect my solution! i have no audio on FS and i can not detect in which problem is! any suggestion?! anybody helps me?! RTP packets sent from FS don't reach my client! RTP packets saved with tcpdump in FS server after being decoded via WireShark play appropriate sound(ivr-demo) for me! My FS NET architecture: FS <> internet <> NAT <> Client (linphone, 3cx ...)