Hi Nir, I use SBC, (ACME PACKETS) which handle these scenarios of NAT. When i use soft phone in the same network with the same network topology everything works fine and i don't even need the use of a STUN. So unfortunately i don't think the problem is the NAT. Maybe you can think of another reason..? Regards, Maya -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20100304/acd842ed/attachment.html>