why are you even using iTunes?
I personally do not like that program
Quicktime will handle your 24 bit files you can open the original WAV file and play it
of course if they are tracked out you won't be able to play them consecutively
or of course you can open them with editing software like:
Audacity/Amadeus Pro/Sound Studio etc. and play them there
I've never had a problem with my 5 year old iMac recognizing my P-2 via Firewire
that's odd that you are having trouble