Need a bit of help here as have been trying to sort this for a number of days.
Have read as many posts as I can, but cannot seem to find a resolution specific to my issue.
The issue is as follows.
Running Freepbx on a dedicated box on a local LAN behind a router/firewall (D-Link D-615 C2)
All internal calling between extensions works fine (using PC based softphones internally) and calling out through external VoIP provider works fine (pennytel)
The issue comes with my remote softphones (running on iphones) when outside the office environment
I can make calls from the remote softphone back into the office extensions no problem
I can make calls from the remote softphone, back through the office system and out on the external VoIP provider no problem
I cannot make calls from within the office out to the iphone softphones (running on Telstra 3G when out of office).
When I am on external 3G network and force the softphones to re-register, my softphone clients running locally on the PC will show the remote phones momentarily connect, then says they go off-line within a few seconds. If I am quick and make the call when the local PC softphones pick-up the remote registration, I can make the call, but as soon as I hang-up I cannot make any further calls out.
The Freepbx System Status shows the remote softphones as on-line all the time when they are there and off-line when they are off.
Funny thing is, if I bring the iphone softphones into the office environment and hook to the local wireless LAN, the system will fully function, even with the external IP address and everything still set on the iphones, so could it be the way the iphone/3G combination works and staying alive?
My extensions are enabled for NAT and the system knows what are internal/external addresses.
Have tried multiple softphone clients on both the PC and Phone
Have tried with and without STUN, but not sure if I know what I am doing with that. On the Bria softphone client, they say not to rely on their STUN server, so not sure if I have actually used stun.
Any help much appreciated as I am pulling my hair out.
PS Just been looking at the SIP peer information under the Astericks info in reports. The host IP that is showing for the phone when it is in the field and registered, looks totally different (126.96.36.199) to what my phone tells me when I run a check on “whatismyip” from a browser on the phone (188.8.131.52) It also says “possible proxy detected” so that maybe where my issues are coming from, though no idea what to do about it.