big bang,you have to do these things yourself or people can phuk with you, get a screwdriver that fits the screws that hold the sub in and take the sub out (8 screws) look at the wires, there is red terminals and black ones, are they BOTH connected? connected to each other or crossways? you have to look, dont be afraid, if your carefull not to poke the screwdriver thru the sub you cant damage anything, when the sub is out play t at low volms and ssee what its doing. do it now and repot back before the store robs you.