My iPod charger broke recently so I used an older one.

When I plugged it in to charge it turned the iPod on normally like it was going to charge but it didnt make the charging sound.

I just left it there hoping it would do something, so I came back to the iPod and then it was turned off, so I turned it on. Somehow it's fully charged but there's a problem... It's rapidly dying. So is it the iPod or just get a new charger.

Anyone mind explaining what's going on?