I had a problem where when I’d be browsing in FireFox with iTunes playing in the background on my MSI Wind u100 Hackintosh. When I was viewing a page with many Flash objects, or moving quickly throughout a page in FireFox iTunes would start stuttering on playback.
Note that I’m using the MSIWindosx86.iso image with no OS X system updates (still on 10.5.4) but all program updates applied. Also I am currently overclocked by 8% with 1 GB of RAM. I tend to think the stutter may be caused by excessive disk swapping so I’m curious if my RAM upgrade will completely eliminate the issue.
I eliminated most the stutter by simply unchecking the “Sound Enhancer” in the Playback section of iTunes Preferences. This setting is on by default. Oddly I still get random stutter, but it’s much less now.
Of course you can go the route of updating your Wind and dealing with broken devices, etc. But I’m happy with my 10.5.4 Wind with all the various pieces of hardware functional.