Bootcamp-Soundcard issue?

[mmmdonuts]

I have an imac late 2009 and have bootcamp and have recently installed windows 8 on it. My issue is the sound on it is really ****** coming from the soundcard i presume? it's playing sounds and music but it's like it's in mono and not as nice quality as when i'm playing music when i'm using my imac side of things. Iv'e had this problem no matter what version of windows i have installed on bootcamp previously but it's starting to get annoying. Obviously plugging in speakers or using headphones is fine but just trying to find out what the go is with the speakers on the machine. I have the latest realtek drivers

Constructive suggestions please?