SX 50 satilite phone trunk

[Kornrows73]

I'm hooking up a satillite phone (Iridium 9505 with base) to the phone SX-50. We are able to pick up the outgoing line and dial through (via line pools). With incoming calls it rings seven times and then the Satphone says its connected and stops ringing. if we disconnect the Mic from the sat phone it rings through immediatly but you can't answer the incoming call.
any help will be greatly appreciated.

 

[pandabear1]

I know nothing about the sat phone but if you put an analogue set on does everything work ok?
Does the sat phone recognize the discriminating ring (double ring)?