I have a jl audio 500/1 amp and for some odd reason its making a crackling sound out to the subwoofer, the amp works fine it's just that it makes a crackling sound, i even unpluged the rca's and still making the crackling sound, even tried it in a different car and still the same thing, even a new subwoofer and still the samething, does anybody know what could be causing this. I've been told that its something in the amp but nobody knows, any comments would be helpful. Thanks