Hello everyone, I have a Mitel 3300 MXE III and a MBG that is configured with SIP. I am trying to extend my ipphones (6920) to remote sites via IPSEC VPN Tunnel, with a Mikrotik on the main location and others on the different remote sites. I also have a Fortinet Firewall on my main site. If I call from my main site to the remote site via extension it works perfectly, also if I call via extension from a remote site to another remote site it also works perfectly. If I call from a cellphone to the remote site it works fine, but if i make a call to the outside from the remote location it doesn't have audio and like %10 of the time it works. I've assigned the subnets of the different sites on the trusted networks of the Mitel 3300. I can ping the phones from the Mitel 3300. The only way it works is if we change the option 'Force sending SDP in initial Invite message' from 'YES' to 'NO' on the PBX, but when we do that, on the main site the calls begin to drop.
