iTunes "warbling" when playing MP3s

I've recently bought an iPod, and I thought I would give iTunes a go at being my everyday music player, since I'll probably end up using it for the iPod anyway. All my MP3s sound extremely screwed up when played with iTunes, but they play just fine in Winamp, Windows Media Player, and the iPod itself. It's hard to describe the sound other than to call it a "warble". You can listen to it for yourself:

http://spine.cx/blog/2006/iTunesWarble.mp3

Anybody have any suggestions? I've upgraded to the latest version of iTunes, 6.0.4.2. I'm running Windows XP Professional w/ Service Pack 2.

IBM Thinkpad T42 Windows XP Pro