I am new to all of this; so here we go. Just purchased an entire setup. Bought the Rane TTM57 & 2 technics running through a mac. Everything was working fine for two weeks. Then turntable #1 wouldent output through the speakers. It would come through the headphones and it was being read by the mixer and laptop. When I turn the mixer off and restart it will play for about 5 seconds before sound cutting off. I can swap them around and get both tracks to play off each table at a time but never together. I returned the mixer and got a new one; set it up, worked for about 2 hours and now same problem. I called rane and they said i should check the cables; they are brand new so idk what I should do!?