Forgive me for being an idiot about this.
We are running FreePBX 14 (up to date)
The server is a dedicated unit, with dual NICs. SIP trunk provided by Spectrum. All internal phones are on a dedicated 172.16.x.x network, and the server has a second nic on our business side so we can access the Dashboard.
We have a remote employee starting. They are running Zoiper 5 until thier new physical phone arrives.
We created a new extension with no presently applied template (Her real phone will be a Yealink)
It presently is the most basic of setups, no VM, call forwarding, no follow-me or anything. Just a single extension and assigned to her user.
We made rules in the firewall for SIP on our ports, and the RTP UDP range, and created a rule that allows the remote employees computer to talk on said ports to the phone server through the business side.
The Zoiper software shows it is connected to the server. When she tries to dial a number, it will ring my extension, and when I pick up, there is dead air, no audio at all.
Have I missed something, or is this up the road of call Sangoma and get more support credits.