Hi,

this problem has been discussed in a few threads here and many other forums. But the suggested solutions (e.g. progressinband = yes) do not work for me.
My setup/tests:
 - Atcom IP02 device with latest switchfin compilation applied
 - 3 local extensions 6000 - 6002 .
 - 1 VFX trunk
 - inbound calls get all routed to ext 6001
 
 - Internal calling is possible
 - external calling is possible to national and international landlines and cellphones
 - internal transfer and call forwards are possible
 - inbound calling from cell phones and landlines is possible

 - Follow-me is possible to cellphones
 - diverting the call via extensions.conf (exten = s,1,Dial(${VFX_trunk}/<target#>) ) works
 - Call forwards initiated via phone (302 "Moved Temporarily") fail with no audio. Signaling/ringing works and the first button press accepting the call works too, but no conversation possible as both ends are just silent.

The audio fails only, when the call is initiated from a TNZ cell phone (tried 2degrees which is working). The cfwd destination is alos a TNZ cell phone.
In order to avoid the firewall, I made the PBX the DMZ host, i.e. no firewall to the internet just NAT (and 1-to-1 PAT).

Did anyone come across this problem? And if so did it get resolved? Otherwise, can anyone guide me the right path to troubleshoot this, please?

The CFWD functionality is required since we turn this on when we leave the office. This is a pre-programmable button at the extension phone, i.e. no website login for (de-)activation.

Many thanks,
--
Stefan