Outgoing external calls: ok
All incoming calls: ok
Outgoing Internal calls: not ok (4-digit number calls from TA1600 to another phone (Mitel SIP Phone 6867i) in the same subnet, no Firewall)
We are in progress of setting up a new Yeastar TA1600 (10.90.11.20). Most of the functions are working well like getting calls or placing a call to an external party over our SIP Trunk (10.90.11.3). PBX is a Mitel MiVoice 5000 (aka as Aastra A5000) on address 10.90.11.5.
But we can not place a Call to another SIP Phone if it is an internal SIP Phone. The remote phone is ringing, but if I pick up the phone, the connection gets dropped immediately.
If I place a call from the remote phone to the phone connected to the TA1600, everything is fine.
I would be very happe if you could help me