When I installed Windows 7 Beta (Build 7000) on my early 2008 MacBook yesterday, the audio driver did not work. The driver provided by Boot Camp is not the right one. Using the hardware id, I learned that the audio card is made by Realtek. I downloaded the driver directly from Realtek and it worked. Here is the download link. The one I downloaded is Vista Driver (32/64 bits) Driver Version R2.14. Extract the files and run the setup.exe.BTW, if you are looking for some older versions, you can use this ftp site.ftp://202.65.194.211/pc/audio/