Audio Systems: Power antenna, power antenna, antenna wire

Question
This is probably something simple but i have been working on this sound system for a while and just can't figure it out.  I have all the speaker wires hooked up correctly, all the ignition and power wires.  The head unit gets power and the amp gets power but i cannot hear anything.  If the power antenna wire gets crossed with the 12v power wire i can hear the music...  
Any suggestions?

Answer
need more info.  when you say the power antnna wire, I'm assuming the wire marked for power antenna going to the cd player not the power antenna wire for the car right?

Do you have a meter that you can test the wires here?  If not please get one,  I got one for $18 and it works great.  you can find one at Walmart, homedepot, autoshops, etc.

what is the model of the cd player?  what happens if you connect a speaker to the speaker outputs on the cd player, does it act the same way?

Thanks