American Audio 10mxr problems

This mixer works fine at home and practice but at the club I have nothing but problems. I get constant tracking problems. Thought it was dirty needles from all the dust in the club. But the other. Djs use serato with no problems. Sounds gets worse as the night goes on even after unhooking turntables and going straight MIDI. Just wondering if anyone else is having issues with this mixer and also can I buy a soundcard to bypass this mixers soundcard?