Hey everyone! I have been scratching my head at this one for weeks. I found the problem in my particular case. When you reboot your Mac, if you have a Logitech (perhaps other also) microphone in the USB port, when you start VMWare Fusion, you get no audio. The device appears to be working properly, however, no sound is present. This problem is corrected by unplugging the USB microphone before you need to reboot, and plugging it back in after Fusion starts back up. Fusion is able to detect the new presence of the microphone after you plug it in after already started. Hope this helps SOMEBODY out there, as this has been frustrating for me for a long while now.