Setup:
3CX Version, Professional 16.0.8.9
W10 Pro, only local Lan, no VLAN, noch changes in hardware setup (Switch etc.), no STUN
Is the 3CX Server Hosted and where? local
IP Phone Make/Model/Firmware 10.1.73.16 Snom D717
Provisioning Method: Loca
Trunk Provider or Gateway Make/Model Sip...