XDJ-RX Output Issue

I am having issues with my XDJ-RX outputs. It’s sounds like there’s noise cancellation but only on the lower frequencies.

It only happens on the booth output. I have tried different cables and output devices but the problem remains.

If I pan hard left/ right on my amp the audio is restored but only one one side, obviously. If I unplug left/ right output cable the audio is also restored but only on one side as before.

I’ve had the RX for just over a year now and this has only been a problem over the past few weeks. The only difference that I can think of is that I recently updated the firmware, it has however worked properly since then.