Hi, We are currently having problems with inbound audio or incoming external calls when we use the 3CX PBX behind our Fortigate FG50B so was wondering if anybody has had any success with the 3CX system behind a Fortinet device. We are using sipgate.co.uk as a voip provider for our external calls. We have a Netgear DG834 Router with ZEN providing our ADSL line Everything works OK when the 3CX system is hanging straight out the back of the ADSL Router. Things start to go wrong when we introduce the Fortagte 50B We have a static IP address We have opened all the recommended ports from 3CX point of view and sipgate's point of view as far as we know. We have set up virtual ip's for each port range and added it to the inbound policy Ports open inbound are 5060 UDP 9000 - 9015 UDP 7000 - 7500 UDP 5481 TCP - Management consol 5004 10000 UDP We have even as a quick test opened all ports on the Firewall TCP/UDP and are still unable to dial in or recieve inbound audio. Outbound calls work but with no inbound audio We have ensured that the firewall uses a fixed port We have also turned off the SIP helper on the Fortinet box using the CLI The 3CX Firewall checker does not complain of any issues I would be very grateful for any help!