okay, my Second Generation iPod Mini (blue 6gig) isn't getting the best battery life anymore. According to Apple i should get up to 18 hours, im lucky if i lasts through a day of on or off usage. Apple says to test the battery by loading an album and letting it play on repeat until the battery dies. i plan on doing this tonight or tomorrow, but my question is, how dead does the battery have to be for Apple to replace it? is half the expected life or less the general rule or what %?? i dont want to bother sending it in if they won't replace it. but its frustrating to have the battery life so low after such a short period of time.