One way VoIP behind pfSense
I am in a little conflict with a pfSense 2.4.4 installation.
The pfSense has two WAN connections, gateway groups and can failover. When the outgoing connection is the Vodafone cable modem, everything works without trouble. Choosing the Telekom WAN way, a speedport hybrid router, VoIP connections to our external telephone system are established where the called person can hear the caller but not the other way round. Putting the snom phone directly on an interface of the speedport, calls can also be made without problems.
Installing the siproxd allows the phones to work properly, until the WAN way changes, because the siproxd can only be configured at one WAN interface.
I guess with some simple NAT rules the problem could be solved without the proxy, but no tutorial on the internet was able to help me.
It would be great, if you guys could help me with that problem or give me a hint about how to solve the issue.