I jury rigged a phone jack cord to an MP3 headset plug; NO signal ANY SUGGESTIONS?!

See Details>>>? The problem. I need to transmit audio from a CD player to a Server for On Hold calls. HERE IS THE LAYOUT:
Phone Jack: yellow, red, green and black
Headset plug: 2 wires, each share the following: Red & Copper AND Green and Copper. Who's saavy enough to figure this McGyver Setup??!!