Problems with Cisco ASA 5510 Router. Any advice?

I have a remote phone off a system. I can call to other extensions with two way audio. Extensions that are local can call out and receive calls with audio. However, if I try to call out from my remote phone there is no audio but the conversation does stay up and shows as answered in the call logs. Any ideas?

I should mention the router onsite is a CISCO ASA 5510

These are usually NAT problems…

Do you mean the one where the PBX is or the remote site?

If so, which other router is involved?

Have a nice day!


The Cisco router is the router local to the system. The router in front of the remote phone I am testing is using Tomato. Thanks for the help!

yes, typically a NAT thing. However, did you define and forward appropriate RTP ports on the ASA? I would assume you did otherwise I guess the other calls you mention wouldn’t have had audio either. You could try putting the remote phone IP into the DMZ of the Tomato router, and see if that works. If so, you’ve at least gotten it narrowed down to where to do your tinkering.