waytoosmall,
I have the same problem with my Toshiba. Not sure what's going on. I've been told it could be OS problem or that my OS inadvertently dumps my audio hardware. I can reboot and it will work again, but it will start doing it again soon after.
I did a full format and left all additional hardware off. A tech told me that he has had several notebooks brought in with a similar problem. Each use itunes and so do I. He thinks it could possibly be a conflict there. I'm frustrated by it, too.
Send me a message and we can compare exact issues. You're the first person I've run across with what appears to be the exact issue I'm having. Maybe between the two of us we can figure it out.