Hi everyone.
Just wanted to share my experience and in case another stopped by with same issue. I got the 9" Acer Aspire One about a month ago and everything was fine but one day, the sound just kept stuttering.

Not knowing what was the cause, I started googling around and eventually found out the culprit. DMA... or rather, my HDD (160 GB) went into PIO mode!! Yuck. No wonder sound stuttered...

Anyhow, if you have such issue, the guy here at the following link has a VBS script patch (I have used it and so it's ok) that fixes it.

http://winhlp.com/node/10

Now, no more stuttering sound! Happy computing!