I have two Freepbx Boxes
one Box a
other Box B
both internal on network but different subsets no firewall between them.
i can call site B from phone in site A but i can only hear them for 10 sec. then no sound but they can still hear me.
if they call me from site b to site A i can only hear them for 10 sec. then no sound but they can still hear me.
there is only one Nic configured in each Server with internal IP only.