Hi Jylee - Interesting update. I have a good friend who uses the Ayre QB-9 for his computer based system, so I have listened to it extensively, and I agree that it sounds wonderful.
Your decision to go with Windows 7 on your Mac Mini, given the fact that iTunes does not currently auto-detect sampling rate, is a good solution. Hadn't really occurred to me.
In any case, welcome to the world of computer based audio. Once I got the SQ issues worked out to my satisfaction, I never looked back!