3cx is a popular voip system. I use it in my home.
I am able to call it when i set the SIP Trunk to the home assistant address but it look like it’s missing something with the codec.
Im able to receive audio (from home assistant), the assistant can get the key tone when i press a key, it say it did not understand but it dont seem to be able to receive the audio from my mic …
If implementing a SIP trunk, we can implement extension to different assistant or command/automatisation …
As far as I know but I might be wrong 3CX is very closed system and doesn’t have any API to control/interact with it so no way to develop an integration for it !
Might double check that 3CX is set up to support the Opus codec, as that is the only one HA supports at this time (there’s another Feature Request for other Codecs)