I have a version 12 sp6.1 system I'm trying to setup and am having the following odd issues with the 3cx firewall checker: the firewall checker fails all test because it incorrectly detects my external IP address, and I can't understand why. Background: -System has a public IP and hostname (pbx.company.com resolves to x.x.x.164) -Watchguard Firebox has appropriate rules for all ports and dynamic masquerading nat from x.x.x.164 to the PBX internal IP. When I go to 'what's my ip etc' it shows the correct ext x.x.x.164 IP address. -When I run the Firewall checker, it shows "resolved public IP x.x.x.166" The first part of the range is correct, but it should be 164 not 166. -Under settings/network/STUN server I have the pbx.company.com in the "static public IP field" I'm really stumped here. Any ideas what might be causing this incorrect resolution?