Audio Problems with NAT Firewalls

[DarkLord]

I appear to be having some minor difficulties in configuring my Firewall (MS ISA 2004). Where I can connect to SIPGATE and register etc, I can receive a call to a client extension on VOIP, however neither party can hear anything.

 

I'm a little confused with the UDP settings for the firewall, as when setting up a protocol for say the SIP Protocol/port (5060 UDP) i have 4 options send, send receive, receive and receive send.

 

Which one do I pick and what other protocols/ports are required

 

I have also opened 8000 to 8019 on udp with send receive. but still no joy, but calls are connected through.

 

 

PLEASE HELP