Hi...I have a R93 that only works on the left channel, I have jumped the volume control on the amp and both channels work at max volume so I know the amplifier and transformer assembly is ok , but for some reason with the volume control cable hooked up only the left channel works...the volume control wires (from the pot on the back of the jukebox red and black) connect black to common and red to phono speakers and the jumper is in place from the 2nd and 3rd from the bottom terminals where it says stereo does this have something to do with the jumper being wrong or any ideas why only one channel works with the volume control?...thanks for your help