Weird Click Wheel battery problem!

Hi I have a black and white clickwheel 20GB ipod, which until now has worked fine.
Yesterday I put an album on it after it had charged fully, transferred from the windows PC via USB2, and this ate HALF the battery. Then when i played one song, it ate the battery fully. I then charged it for 4 hours, played one song, and the battery was gone. I phoned apple, they said to determine if its the battery, i should play a random song on repeat. I've done this and its still going after 7 hours! Yet when i play this song on the new album, it drains this sucker.
Any ideas?!
Alex

I would buy a new battery for it, Newertech make the best ones.

I suggest restoring it to factory settings with the iPod software updater and put everything back on again.

Also make sure you have the latest firmware for your iPod.
www.apple.com/ipod

If an iPod update and all that doesn't work, than I would suggest you to get another battery. Plus a new battery now a days would boost your life by 2x if you were to get a new one off the internet and put it in your self.