I have an iPod Classic 120gb and it only seems to charge through a Mac. I have tried charging it with an iPad and iPhone wall charger, Belkin car charge made for iPad and iPhone 4 and these will not charge it. I have a cheap car charger from monoprice.com that seems to charge it in the car but other than that it will only charge through a Mac. Any suggestions? It is about 1 1/2 years old and in relatively good shape , I don't believe it's the battery because even plugging it into a car charger or wall charger should at least power it.