[Cool_V_300C]

Mr. Wicked,

try this experiment.

put the balance all the way to the right.
then put the fader all the way to the front.

while playing music, gradually move the fader from
front to rear.

listen carefully.

If you hear a hole in the sound around time the fader is in the middle
instead of a smooth transition between front and rear, then you
may benefit from doing the reverse polarity trick.

I don't have the kicker system, but this is how I found the problem.

In your case, you may need to reverse the polarity on your rear
deck spears, then test the connection on your sub as well.