Cheap way to get separate party chat and game audio levels?

I have already moved the slider in the party settings all the way to "non-party audio" but it's sometimes hard to hear enemy footsteps in a game like Black Ops 3 when friends are chatting. I have a pair of HyperX Cloud 2s that I love but unfortunately the USB audio card it comes with doesn't work with PS4 very well. I know buying an Astro mixamp would achieve this but those are £90+, any cheaper alternative hardware available?