In copying the music from the iPod to my hard drive after an iTunes crash rendered the iPod inoperable, one or two of these folders seems to have gotten away from me. I don't know what happened to it, but unfortunately that means that there are tracks missing from a vast amount of albums on my iPod. I am currently organizing the copies I made on my hard drive to make a comprehensive list of what tracks need to be restored and what don't. In some cases (Lord of the Rings, Battlestar Galactica, etc.) I already have the music on my computer, others I will have to re-rip individual tracks. I've established certain albums that have not been effected - Legend, Zulu, Heavy Metal 2000, but am still picking up the pieces on several others.
It is extremely tedious.
I hadn't noticed this problem until later because I had just made a new mix, which had been dominating my listening. It being loaded onto my iPod after the crash meant that nothing had been lost.
What really bothers me about this situation is that it was unnecessary. All I needed to do was reboot the iPod O.S., but Apple insures that there is no protocol for doing that without wiping the hard drive.