i have no outlets in my house with the third prong, ground wire...im using a surge protector with an adaptor to fit this 2 pronged outlet...i hooked the rca outputs into the mixer, grounded the tables to the mixer, attempted to ground the mixer to the receiver using a piece of wire, and connected the master output of the mixer to the phono in of the receiver...i am getting major hum and nearly no sound...how do i ground everything properly (and safely)? thanks.