Ok.  Here is an odd one. 
  
In early April 2008, I took my 2007 Edge in for service under warranty.  One of the items that the dealer looked at for me was a mechanical noise that was coming from the radio/CD player at first start-up when the weather was cold.  It was not a big deal, as the noise went away after a few minutes, but since the vehicle is under warranty, I thought the dealer should look at it. 
  
Well - the dealer replaced the radio.  I was surprised that they did this so quickly, but was happy that it was "fixed".  I soon noticed that with the new radio installed, I no longer had bass (or any sound) coming from my subwoofer (I do have the $385 Audiophile CDX option). Oddly enough, I also noticed that I did not have the "Occupancy Mode" option when I scrolled through the audio menu options.  The dealer suspected that the problem was due to a defective radio, so one was ordered.  I took the Edge in for service today, to have the radio replaced.  Today, when the dealer called, they stated that the real problem was a connector that was not connected (I assume a connector to the subwoofer amp??).  At this point, I was fairly confident that the isssue was solved.  However, I picked up the vehicle and guess what? Still no sound out of the subwoofer and still no "Occupancy Mode". 
  
So, here are my questions: (1) are the radio/6 Cd changers identical in units with the subwoofer option?  (2) is the "Occupancy Mode" option tied to whether a subwoofer is present?  (3) is this a matter of programming the radio to let it know that a subwoofer option is present? (4) is my dealer totally incompetent? 
  
Any insight would be appreciated.