[Yossarian]

I am currently importing all my CDs into iTunes. After a while, I noticed that certain song files were only about 40 kb in size. They couldn't be played. Most of the songs were imported in AAC iTunes Plus quality.
I thought this was an error that occurred during importing. But yesterday I was going to play some songs that I had successfully ripped and transferred to my iPhone previously. I had been listening to them on the phone for some time, but all but the first file in iTunes on my computer had become corrupted in this way, with songs taking up about 40 kb.

Has anyone experienced this? What is causing it, and how do I fix it?