I think I might have found an answer - importing a folder and or Limewire!
Either Limewire mess's with the files, folder or your system or iTunes attempts to stop illegally downloaded files being played. iTunes might also do it if importing a lot of files in one go.
I imported a music folder that isn't mine from our home network drive that has a few tracks in it downloaded through Limewire. I re checked some of the files in Ableton Live and they are actually damaged! So I tried importing one of the Limewire tunes again individually after finding some info online (links to the pages at bottom) and the track plays no prob now. I also un-checked the "look for shared folders" in iTunes preferences.
For about 2 years now I haven't been able to import more than 3 files at a time which is why I imported a whole folder (about 50 tracks) just after the software update and C.D importing.
My concern is that importing a whole folder even without any Limewire downloads in it might well be treated this way by iTunes. Most of the tracks in our network drive folder that have been downloaded through Limewire are legit direct connect transfers from producer to producer or legit submitted tracks!
Hope this helps.
http://www.tuaw.com/2007/03/14/limewire-reportedly-unhappy-with-itunes-7-1/2#com ments
http://www.crunchgear.com/2007/03/15/limewire-will-make-a-mess-of-your-itunes/
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