Windows - MBP/Bootcamp Audio Problems

Whenever I need to boot into Windows using bootcamp, my audio goes all weird. For the most part it is OK but if I turn the volume up to high levels, the feedback is absolutely shocking...like a Guitar near an Amp...Hendrix would be proud!

Every now and then the audio is jumpy as well. If I play a song through iTunes, there is occassionally a small blip...like when a record needle jumps.

And a new major problem...if I hover my hand over the left speaker (just near the power in) the feedback starts again - very loud. This doesn't occur in OSX.

Anyone have any idea what the problem may be? I have the latest version of Bootcamp installed BTW.