I have experienced this issue with other games. I have always used a USB headset, but when I added a set of external speakers to my PC and therefore a second audio device, I lost the use of my headset. I use Vista and the only solution I found was to disable the audio device (external speakers), so that Windows only thought I had a USB headset for sound. Rebooted and all was good. If you also do this, be sure to hide your inactive devices if you have Vista. If you don't hide the inactive devices, Vista may provide some meaningless error message on every boot. Hope this helps.