Now it doesn't do this all the time, but on some songs with a little heavier bass than others, my subwoofer makes crackling & whining noises. Does this mean the subwoofer is going bad or is there too much bass? I usually have the bass set just under the half point & my volume is mostly under the half point. Would it help if I just changed the sub out? What would it sound like without the sub?

 

could be a sign of a sub going out or even an amp going out