SIP telephony. One-way listening. How to fix?

Question

Asterisk

Hello. The essence of the question is this: some of the phones work normally, that is, you can hear in both directions, the
other part can hear us, but we can’t hear the interlocutor.
All phones are configured the same (well, except for their local IP and extension number, of course).
Internal calls pass on all with a bang. And external only on a part of them, and today some can work, and tomorrow others.
I enter the PBX settings through the web interface, PBX LAVOICE LVX-100S.
The diagram of how we have everything connected is shown in the image:

Answer 1

Check that NAT is enabled for users in the PBX number settings.
Are all devices on the same network? According to the diagram, yes. Or did you separate 192.168.0.X and 192.168.1.X somehow differently?