panasonic cq-c8400u, no sound

I am trying to install a 2004 panasonic CQ-C8400U into a 2000 Saturn SL1.  I have all the wiring diagram and colour code for both the car and the deck.  I know that I have hooked up all the wires properly and the Panasonic deck does light up and come on, but I can't get any sound from the speakers.  I even did a straight connection from deck to speaker, but still no sound.  I tried the same setup with the old deck and I get sound.  I have idea what to do now.  The only thing that I couldn't figure out how to hook up was the dc/dc converter.  Does that thing matter ? What is it even used for ? Well, that's my delima, can't get any sound from the speaker (nothing wrong with the speakers).

If you did a straight connection from deck to speaker and still get no audio, make sure the mute wire isn't grounded for some reason. I'm not sure if that headunit has an amp cancel built in but you might want to check if it does and if it's on. If that doesn't solve it time to exchange it.MECP Certified

Fry's Electronics MEI - Anaheim, Ca

"Kneel Before Zod"

would you know how to hook up the dc/dc converter ? ... the only thing the manual says about hooking up the dc/dc converter is to consult a specialized contractor  ... I have no idea where to start to connect this thing.