Hello
RDWild,
The audio does go from the IP Phone to the 3CX Server and from the 3CX Server to the Sip Trunk Provider.
So the first thing to know for a fact is where the audio gets lost.
Can you call from one of the 'new' phones to another 'existing' and get audio (internal call)?
Or is it only to and from the SIP Trunk Provider where you have the problem (external call)?
Let's focus on the internal call failing.
How are the IP Phones connected to the 3CX server, is the 3CX Server local on the LAN?
Than focus on the used CODEC, this could be a problem ???
If the IP Phones are connected by a SBC on the LAN that is connected to the 3CX Server (cloud based), than focus on the SBC.
Also here there could be some codec problem.
Let start with some general question:
Type of 3CX server, like: Local, SMB, Pro Cloud?
Brand and type of phone used?
How is the phone connected to the 3CX server? SBC, STUN, LAN?
Paulo