It's perhaps a software bug? So, I suggest you follow these instruction from Apple to reset your iPod. Learn how to reset or restart iPod following a freeze. Tip: Check out this helpful movie too. Important: If your iPod is frozen or won't turn on, it may be because iPod is paused or the Hold switch is in the locked position. If so, a lock symbol appears on the screen. Slide the Hold switch to the unlocked position and check the screen. If the iPod is connected to a computer and displays any of the following messages you should eject the iPod from within iTunes instead of resetting it: 1) Connected. Eject before disconnecting 2) Sync in Progress. Please wait... 3) Do not disconnect If your iPod is frozen or won't turn on, the steps to reset it vary by model. You caneasily tell which iPod model you have if you're not sure.

Quote from mitra:

I like the photo where you show all the parts. It could be on it's own step...

Done :)