DJM-400 Cue Issue

Hey guys, I'm having some sound quality issues when using cuing. If I cue just channel 1, just channel 2 or just the master the audio is extremely grainy and lacks a lot of bass, but if I cue channel 1 or channel 2 while having the master cue button selected the audio quality is fine. Anyone know what might be the cause of this or how I can fix it so the audio quality when individual channels are selected is fine?