so we rearranged our room so we are now reconnecting our receiver and speakers... everything works but the left and right front speakers!! we are using the yahama RX 990 receiver (it is pretty old) On this receiver, you can use two sets of speakers for the left and right. but we are just using only one left and one right. we know it is not the speakers because we hooked up a working speaker to the outputs. what could it be?!!??! the entire "front speaker" section outputs on the back of the receiver doesn't work cause we tried every possible combination. is it a fuse inside?! Is it a setting? I am getting very frustrated. any suggestions?