I have the same problem, but not as you might think.
I had this problem while playing games. I couldn't be heard at all, or my mic sounded TERRIBLE! (as told by the guys I played with)
Later I found out, that the terrible sounding recording was from the internal mic, and I had to do something. I then picked up the sound settings via Control Panel, and got rid of this terrible error.
Now, This is my question to you guys:
How can you prevent SigmaTel Audio from setting "Line In" as default when launching the PC?
I'm sick and tired of the pop-up, but it can't be helped, can it?
Thomas, June 2009