Remote SIP Phone no Audio

Make sure that the external ip address is set in the pbx -> settings -> sip settings
At the pbx router location disable SIP ALG and forward udp ports 10000-20000 to your pbx server
Disable SIP ALG in the home router

Well I can get the transmit to work, but the phone keeps dropping and no reciving audio is working. Any suggestions?

From the dashboard select the pbx tab, select the tools tab, enter sip show peers for the command and hit execute.
What is the results?

I just configured a yealink t28p as a remote extension off a ucx 50e with no audio problems.

I used a generic sip device for the extension, gave it an extension and user name
left everything at default values except for NAT changed from no-RFC3581 to yes
saved and applied the configuration
insured that the router at the pbx location had SIP ALG disabled and the ports UDP 5060 and 10000-20000 were forwarded to the address of the pbx

configured the phone with the extension credentials and the server host address of the remote pbx
applied the configuration and the phone registered

both in and outgoing calls have audio in both directions