Hi there. Ive been using the 3CX phone system running on windows server 2003 for many years without any issues on version9 and on a using a netgear dg834 router. I had to reformat the server last week and i also upgrade the router to a Netgear DGN3700 N600. Have installed windows server 2008 and the latest version of 3CX phonesystem and restored my backup. The phone system when we make outgoing calls has one way audio only but works fine if somebody calls in, however some times even if someone calls in it is one way audio only and the digital receptionist doesn't play to the caller its just blank. I plugged in my old Netgear DG834 router and everything started working fine. So back to the new router, i have opened all the ports necessary as stated on the 3CX website and also ran the firewall checker in 3CX phonesystem which it shows all checks passing OK. Can anyone help me shed some light to this mystery or what I haven't configured right on the new Netgear DGN3700 Router. Thankyou in advanced.