Wierd, after a lot of tweaking about, I found out the cause was either having the mp3 already stored in the winamp bookmarks, or recently played section, so erasing all those sorted the problem.
Edit: Argh, ok... it worked for the playlist, not the media lib list.
Edit2: It changes in "Top Rated" now, think I will just reinstall winamp.
Edit3: Reinstalling worked, rather have fixed it in finding out the problem, but oh well.. cheers.