Just noticed this today - I had downloaded several songs from iTunes to a memory stick and was playing them in the car, but noticed two were missing. Brought the memory stick back inside, plugged into computer, and there they were. Played fine on computer, but seemingly invisible when in the car. I noticed that each song was French, and had an accented é in the title (Fauré, and Sa Nuit D'Été). I just renamed them on the desktop to Faure and Sa Nuit D'Ete (no accents) and then tried them in the car again and Voilà! - they reappeared. Anyone else notice this bug?