How to change the drive letter in a dual boot computer

What do you want to say with that? The video driver is responsible for the sound?
Aero works well,but only if Media Player is working on the background of the guest (Vista x86 has a base score of 4.1 and x64 has a 4.3 one).I have to do something in a VM that needs sound.That's why I want to know how.When I was watching a DVD in the VM,sound was a disappointment.It had crackles and it was distorted.

Can you understand what I say? Aero doesn't have any problems,if Media Player is working and Tools are installed.But sound still has distortions.I want to know how to fix it (don't give the VMware article which says select 24 bit 44100 Hz,I have done that).

When I say distortions you can understand what I mean with that word.For example,the DVD,while it was playing,the sound had crackles,as if you had a blue screen.Yeah,the sound will sound like that.See a YouTube video named "Windows Vista sure likes Blue" and you will hear that sound.Then you will see what happens.
I think you know that a blue screen won't occur.

Yes.Virtual PC.Sound problems are gone from Virtual PC.However,Aero isn't working in it.VMware has full support of Aero,but sound is distorted.

Hello? Sorry for doing that,but I haven't received any answer from anyone.
If you want to know about the situation,sound is still distorted (in VMware).