Toshiba Satellite P100-347 Audio Problems

[MSIuser]

Hello,

I have just purchased this laptop brand new and I'm having a few problems with the sound. It has a Conexant HD Audio output (it basically has a headphone jack which can also give optical output). I am currenty listening to music (mp3 played through foobar). I know the mp3 is not the problem because it is exactly the same file I was listening to on my old laptop and had no problems. The problem is that every now and again the music sort of jumps and distorts, it's hard to describe but it doesn't sound normal. I have also tried using the optical output hooked up to an amplifier and it still does the same thing. :S Does anyone have any ideas why or how I can fix this? It's really frustrating when the laptop cost me £1400 and I used my old laptop to listen to music all the time.

As a side issue does anyone know how I can use the optical output to get surround sound from games such as counterstrike:source? I can get surround output when playing a dvd through an application which has an option to use spdif output but most games don't have this option in them. The jumping thing isn't as noticeable in games but every now and again i notice it.

Laptop Specs:
Intel Core 2 Duo T7200 2Ghz
2gig ram
GeForce Go 7900 GS
running Windows Media Center with all updates installed

I think the Conexant HD uses the Intel HD Audio Bus (don't really know what that means but i remember seeing it somewhere when i was being nosey in the settings trying to fix it).