DJM 600 sound issue

Left side works on 1 with either input and on channel 2 - 4 with the CD2/line (left position) input only but doesn't work on any other input (right position - phono). Right side does not work on any inputs on any channels. I have changed cords and tried on a previous mixer of mine and it works fine so it's definitely the mixer here. what is wrong with my right side inputs. It registers sound coming into the mixer normal on CD/Line input (left position) on channel 1 and 2 but if you switch the switch to phono (right position) it shows way too much signal. and it does that for the left side also when the input selector is on the phono (right position) for channels 2-4