As the title says, is it possible for a sub to be ruined mechanically/internally (i.e. not work anymore or produce good sound or any sound at all). I'm talking right out of the box, brand new. I'm posting for a friend I know, he bought two 10" Audiobahn subs for his truck and one doesn't work. The guy at our local audio shop said the "sub is dead." The sub has no damage visually. Is it possible for a sub to get ruined from exposure to certain things. For example, if you put a floppy disc near batteries for a while they get ruined...anything that can ruin a sub?