53XX IP Phones Nat to the 5000

[jmarx33]

I have a problem with remote IP phones that we just setup for users to work from home, this is a CS-5000 system that used IP phone internal with no problems and two of them need to work from home so we set up 1 to 1 Nat both to the PM and the PEC-1 with the correct ports to be opened on there firewall that is a sonicwall that there IT person programmed the Nat. The problem that I'm having is with the remote phone as a test from my office the phone connects and if a call another extension I can hear them but they can not hear me and on the phone Insufficient Bandwidth pops up, called tech support and we went over the IP connections information as well made sure the extension was set to Nat. Does this sound like a firewall problem on the sonicwall not setup right and has anybody had this happen to them with a sonicwall?

[Tech Electronics]

jmarx33,

First off make sure that the remote phones are not in a Network Group that uses Peer-To-Peer Audio.

System > Devices and Feature Codes > Network Groups: Are any set for peer-to-peer audio?

If there is then drill further into the group an see if you can find your remote phones under the Phones section. If they are then just put them in a Network Group that doesn't have peer-to-peer audio set to yes.

If that doesn't fix it then let us know.

Thanks,

TE

[jmarx33]

On the remote phones they are not using peer to peer as they are in it's own group.

[Tech Electronics]

jmarx33,

Then most likely the Sonic Firewall is doing some sort of transformation on the packets that is causing a breakdown in communication. This happens a lot with Sonic Firewalls and SIP so you have to turn off SIP Transformations to get it to work.

Have the temporarily do a true 1:1 NAT and turn off any sort of inspections on the traffic and see if the problem persists.

Thanks,

TE