[eia1989]

Well, i did many of the things listed here, and i thank you all!
Seems like many people is experiencing this problem..

Anyway, i read someone mentioning windows update and i have experienced the same thing! The sound dissapeared when my windows update thing started to act weird. Now i allways get this shield(!) and even if a download and try to install the update, it never goes away.
So i did what someone said, and made windows notify me before downloading and installing an update, and it seems to work for now!

And this reminds me that i got the same problem before once, i think it dissapeared when i got another windows update, which i managed to install.. Really weird this!