Hello everyone! I've got the 3CX Phone 5 installed on Windows 7 Ultimate, x64. If I place a call everything works fine, audio and everything. However, as soon as I put that first call on hold and place a second call, that second call will have no audio at all. It's an external extension. DMZ enabled on the router. Set to use a different port (5063). What else could it be? Why does the first one have audio and not the second one?, please some help.