The problem that I am experincing is that when the songs crossfade from one to the other the second songs sounds briefley like it is skipping. I repeated this several times and I saw that the colum showing the song statistics (like the number of times the song has been played etc.) is updated while the song sounds like skipping. I think that the library is being updated inmediatelly after a song is played and while writting to the disk Itunes can't keep up with a good reproduction of the song
I don't know what happened with the crossfade function, in previous versions of iTunes crossfade worked perfect. Now I have the same problem, it works randomly, mostly only for the songs in playlists. If I try to test it by dragging the song-time to the crossfade time, it never works. ****, i have the OnCue Pro app on my iPhone and it does the crossfade with no problem, even the testing, but my MBA cannot do it.
Hope Apple fixes this very soon.