No audio when calling in systen phone numbers

Weird issue, we have multiple locations on one pbx system however when one location dials the full phone number of another on system location instead of the extension (Crazy i know), there is no audio. All audio runs fine otherwise inbound outbound etc. Seems as if the issue has been gradually happening over time as it worked fine a bit ago. So not sure whats up. Any other questions feel free to ask. Router is pfsense.
PBX Firmware:
1.811.210.57-1
PBX Service Pack:
1.0.0.0

What sort of trunks are you using for outbound/inbound calls? Are they SIP or IAX2? Who is the provider? Is NATing involved?

Sip trunks through Voipinnovations term/orig. yes they are natted however, like i said all external extensions work fine via calling extension to extension or inbound DID outboud etc.

It could be pfsense not allowing traffic back in to the outside interface of the firewall because it originated inside.

I think your right by default port reflection is off, thanks for helping me find that out.