Headphone Cue not working properly

So, I recently got a new laptop (Windows). I have a DDJ200 and splitter cable.

The headphones play a muffled version of the master ouptup constantly despite the master and headphone cue butons not being clicked and also play muddy versions ontop of this when headphone cues are utilised to monitor.

I'm unsure what to do and need a fix. I have a realtek driver and a Sound Blaster 6 soundcard if that means much.

My outputs currently show: