Lack of sound

That's a very safe bet. The factory deck doesn't have enough juice.

If you talk to any serious sound guys, the deck really shouldn't ever be used to power speakers. Pick up a small amp for the speakers and that should do the trick.

Sorry to hear about the face plate getting stolen. Have you contacted pioneer to see if they can send you another face plate?

Dont bother talking to pioneer about getting a new faceplate, they will charge you mad cash to get it, you would be better off to get a new head unit. I had a buddy that had his faceplate stolen (sony) and he called sony to order it, they wanted $140 bucks for just the faceplate, seems a little steep to me. Why would anyone bother stealing a faceplate anyway, not like its gonna do them any good anyway, unless they lost there faceplate and it was the same model. Moral of the story, take your faceplate with you or hide it in the car when you leave.