On the Mikrotik 4011 router, I have a firewall default and in the LAN network there is a telephone exchange.
Whenever I make an outgoing call, the person on the receiving end cannot hear me, while I can hear them.
Similarly, when I receive a call from somebody, I cannot hear them, while they can hear me.
It seems that the person on the receiving end of the calls cannot hear the caller.
Does anybody know what is wrong and how I can fix this?