I am a new user from Germany. I have installed a 3CX phone system. I have a dynamic IP; so I use a software to make it a static IP. I made the port 5555 open and use it instead of the 5060. I am able to call everyone, but within my network, i can hear the other person talking. But if the person is from some other part(not in my network), he is able to register his softphone, but not able to talk to me. we are getting connected, but still unable to talk. Kindly help me.