I could be playing Ray Charles only to be rudely interupted by the caterwauling of Cindy Lauper.

Did you happen to download that Ray Charles song from a P2P file sharing service?

The thing you describe sounds suspiciously like something that some people have been doing in an attempt to kill the P2P services: Deliberately screwing up MP3 files and putting them up on the file sharing services.

The idea is that people will download the song from the service and listen to the first 30 seconds or so and will be convinced the file is good. Then they will leave the file available for download and it will continue to circulate in the file sharing service. By screwing up the song somewhere in the middle, and only for a brief instant, the perps are ensuring that the file will only be discovered to be "bad" at the most irritating moment... when you're actually listening to and enjoying the song.

In this way, they hope to make people doubt the integrity of the files they get on these services, and therefore stop using them.

Then again... you could just have some cross linked sectors on your hard disk...