Certain things volume doesn't work with

Hey guys! I have a macbook pro, and ive been running windows on it but i have a slight problem. My volume seems to work with games and i can hear it when i click the buttons to make it louder, but it doesn't work with anything else such as youtube. I had this problem a week ago but i got it to work until i had to re-install windows to get more hard drive space. The problem was always something to do with the enchantments on the volume control, but i tried everything and still cant seem to fix it this time. Anyone willing to help me? Cheers

Have you tried to update your BootCamp drivers for Windows?
http://support.apple.com/downloads/#bootcamp

Nope! But when i try to download the Boot Camp Software Update 3.1 for Windows 32 bit, it wont let me because it says i need update 3.0 or earlier, and i cant fine any earlier updates