I'm fresh in this subject and I have no orientation how to do. Our small community bought dual cd player ZDX-300 and audio system Model APA-7200( include mixer + 2 speakers). Mixer has one stereo RC input and 7 microphone inputs. Dual deck cd player has 2 RC sereo outputs. Everything is working fine if I connect just 1 output from ZDX-300 to the input of the mixer, but if I connect 2 audio stereo outputs from ZDX-300 to one input of mixer using "Y" connectors I have terrible noise during playback from any of the cd deck.
What I have to do to get a clear sound and use two decks. Please advice.

Thank you
xnigma