My 3G 20GB ipod makes noises constantly when its not even in use, these range from high pitched whining noises i can hear from a metre or so away to quiet blips and bleats only audible if i press it against my ear.

I've had the ipod for one and a half years now. Also sometimes when i select a track to play it will either skip it and play the next one down in that album or it will go back to the main menu (if that track was the only one in album?)

Whats gone wrong? I read somewhere that noises like this mean the harddrive is about to die so I'm a bit worried