Classic and non-Classic apps work great. Play sound files, play CDs all fine. I get the start-up chime, but after that, nothing. I've posted this bug a million times but few people seem to know. If it doesn't know any KEXTs loaded you need to remove all unecessary hardware and try again.
Some hardware prevents KEXTs from loading.
I have this problem with the Cyborg 3D USB jotstick. I can confirm the USB mic with Via Voice symptom. Saw the previous post about unplugging the USB mic. The solution is to remove all unnecessary hardware. Alternatively, the page also includes a link to an Awacs Audio Driver that is an easier way to accomplish the same thing.