3CX Phone System disconnects

[craigduff]

I am using 3cx behind a pfsense firewall, and the only issue i have is that when i either make an internal call or external call the call disconnects after 32 seconds. Looking at the logs, it looks like the ACK is not being recieved. I am using a soft phone externally connecting, if i create a VPN or locally do it, everything works well. Any suggestions? All ports a forwarded onto the SIP server.

Thank you in advance.