Got a new re audio srx 12 inch dual 2 ohm I wired it 4ohm but when I test my wires going to the amp it reads 6.8 ohms. I double checked the box and it states dual 2 ohm not the 4 ohm one. Anyone had this problem with the srx 12? Or any other sub? Did I just mess up the wiring or r they just high? Any thoughts?