You know what the song is though, right? I would suggest you look in the database for that song. My guess is you'll find it.
Here's what I think is happening: You have two mp3s on your iPod. One of them is correctly tagged and its the one you're looking at with winamp. There's another one (Perhaps in \recycled\, Windows loves to put stuff in that directory, but it could be anywhere) that has no id3 info. I don't use the database, so I don't know the answer to this question, but can you see the file path in the database, or while listening can you some how bring up the file you're listening to, say via a WPS that shows full path? I'd guess that you're not listening to the file you think you are.
The other option is you have something weird going on with your id3 tags. perhaps some strange character in them that is giving the Database fits. But I can't help you with that. I'm just a lowly artist