"Some times when you drop your ipod the lens inside skips. (kinda like a record player) reset your ipod by holding the middle and menu button until you hear clicking. then with one hand hold the ipod firmly and hit the side of it onto the PALM of your other hand. Sometimes this jumps the needle back into place but not all the time."
Wasn't easy for me, but at least my ipod returns to normal 🙂 (it is working!!)