First, in the 'V' channel of the radio control bar, put your game ID in it, then press and hold down the 'T' (assuming you have not remapped the function) key while talking into the mic.
When you do this, you should see your name in the upper left corner of the display, and hear yourself over your speakers/headset.
If none of that happens, check the microphone device in the games Options->Preference->Game Sounds panel to be sure we selected the right device the microphone is attached to.
If all the above checks out and it still is not working, it could be a firewall preventing the sound server from attaching to your computer over the Internet. Try disabling the firewall, for a moment, and try it again. If it works, you know where the problem is.
Last, but not least, there are routers that simply cannot handle UDP over NAT, which is what we use for our VOX system. Check with the router manufacturer about this one.
Hope that helps.
