Quote Originally Posted by burris View Post
Would you guess then that those of us who have major port forwarding enabled for many years now, can disable the port forwarding?.
I used to have dozens of port forwarding rules setup on my router for each of the RTP audio providers, it was a real pain especially when I found a new one (one way audio) and had to go add the port forward rule and redial or have them call me back. I finally just gave up and port forwarded all UDP traffic on my RTP ports to my SPA2102 and haven't had any issues since. I did change the RTP port range from the standard ones to a different range and also the SIP port numbers on my SPA2102 just to avoid any issues with random calls from hackers that I've read about on other message boards.

But to answer your question - if you do require port forwarding on the RTP ports you can try just setting it to the ones I posted above for outgoing calls and for incoming calls I am seeing 174.36.46.53 (verify that these are the same ones for you). This should work until they change to proxies and you get one way audio..... Or just forward everything like I ended up doing and if you get strange calls then change the RTP ports to a different range.