Reply to Numark problem

Just bought a numark m2 mixer to go along with my sl1 and str8-100 turntables. When i play music with the turntables, the sound coming out of my Harbringer speakers sounds extremely distorted. any ideas on why?

my mixer is connected to my speakers and the sl1, the sl1 is connected to both of my turntables and my computer.

whats wrong with it?