Rear door speakers no worky

1995 xlt, premium sound system. Had to run and splice in my cd changer to the radio antennae head in the passenger rear (WTF?!) which required removing the rear seatbelt, cowl etc....could not find anything as to why my rears dont work. My factory sub works, as do the front spkrs, but where would i start to look? also I cannot set the rear access to sound controls (buttons 3 and 5 together) thanx all!