I got an Ipod classic 120 gb that everytime i try and sync it itunes freezes

The point of this event is on an average somewhere around 35 songs, give or take a few due to file sizes being transferred to device.ipodf reads 489 mb is used It hits that point itune is no longer responding and have to shut down computer and reboot.The ipod will have installed all music up to the point of the crash also having all its function just only get two albums for use. Does anyone know what is going on here and what needs to be done?