I am having issue for one way audio problem, but its problem for only outgoing. Now I am running Elastix 2.0.3 with freePBX 2.8 and Asterisk 188.8.131.52. The problem is: I have remote extension setup with Linksys SPA3102; and I sent to different country. It was worked OK. Until last October 2010 I didn’t have any problem (they can make calls and receive calls no problem.) After October 2010, When they make a calls (outgoing) the receiver can hear only 20 to 30 second (some time only one way audio) and the calls cut off with in 20 to 30 second. But when they receive the calls they don’t have any problem. I am confuse, If that country block the VoIP it shouldn’t work both ways (incoming and outgoing) am I right? In this case they don’t have any problem for incoming calls. I did all the troubleshooting for their router. I disable the firewall and I open the port 5060 and RTP 10001 to 20000 for their router. If it's NAT issue why they don’t have any problem for receiving calls? I have 5 more remote extensions running different countries, I don’t have any issue. Please please help me to resolve this problem. Anything else do I need to do?