Still can't get the harness to work!

I got this harness from Best Buy:
Metra Speaker Connector for Select Volkswagen Vehicles VW-9000 - Best Buy

I tried wiring it exactly color to color, and no sound. I then tried switching the red and yellow wires, still no sound. Lastly I tried connecting the remote out wire to the blue/grey wire that was plugged into the A5 slow on the plug coming from the car. Still nothing. What am I doing wrong?