Huge VOIP/SIP problem with FVS336g v2

[izzyb]

Our FVS is configured thus:

Four vlans, one per LAN port.

Vlan9 is bound to port 3 and is the phone/voip subnet. Our Cisco UC560 pbx is on that subnet, as are all our Cisco 79xx phones.

Our core switch is a Cisco 3650 POE Catalyst.

Internal calling works FINE. I can call an extension from any other extension and there are no issues.

However, when I try to call out, there is no voice/sound. The call completes, rings, but when the party answers, they cannot hear anything and I cannot hear them.

I have added rules to the FVS to permit SIP-UDP and SIP-TCP outbound for any LAN address.

I have added inbound rules to the FVS to permit SIP-UDP and SIP-TCP for any inbound LAN address. I also added an inbound rule for UDP ports 10000-20000.

What am I missing? Help!

[izzyb]

SIP ALG is not enabled.

[Nhellie]

Is the FVS your main router? Or is it behind a gateway?

[izzyb]

Main router. The only thing in front of it is the cable modem.

[Nhellie]

What is the FW by the way?

Can you try unchecking "Block UDP Flood" on "Attack Checks"?

[RX]

Hi izzyb,

Just a suggestion, check if the ports you have opened are really open via this link: http://www.subnetonline.com/pages/network-tools/online-port-scanner.php