Routing Audio w/ Traktor Kontrol s4 & MPCkey

Working with Traktor kontrol s4 and my akai mpc. I have outputs and inputs routed from both my MPC and my tractor deck. For some reason decks c and d have audio go through just fine.

as soon as I even load a track into decks a or b, immediate static starts. When I switch the deck to live, the buzzing slowly fades away. I don’t even need to press play.

Any ideas ? Output routing in my Traktor has all of the decks the same (assigned to Channel A)