[asterisk-users] Cisco 7960 Double Natted

[Barry Fawthrop]

Hi All

Yes I know double Nat is a problem

But I have a Cisco 7960 which is remote from the * PBX ad connected via 
the Internet. Each side has NAT

(1) Sometimes it will work often it won't. And when it decides to work 
is random

Always
(2) The Register side works fine. SIP SHOW PEERS has the phone listed 
with the correct IP address and an average Qualify time (121 ms)

Always
(3) You can make calls outbound with the Cisco phone through the * PBX

Problem
(4) You can not receive any calls (when not working correctly)
     (a) The Phone rings but not voice goes through
     (b) Sometimes get a 481 "Call Leg Does Not Exist"
     (c) Sometimes get a  -- is circuit-busy

(5) On a reload of the * box you will 95 % sure loose the connection if 
it was working ?

(6)  SIP 5060  - 5063  and RTP 10000 - 25000 is open and port forwarded 
on both sides

(7) All calls are VoIP and terminate or originate via a VoIP Provider

Anybody got any ideas, I have tried everything

Thanks All
Barry