general stereo/amp question

[vw-j@webtv.net (Jeremy Brandow)]

  Hey everyone,
  I have a question, I'm not sure if you all can answer but here it
goes.
  I have a 98 glx with Bose,  I have had Denon reciever mated with the
Bose system.  everything has been running perfect, and I can't beleive
how much better the sound quality is now.  
  my goal now is to add an amp and a sub, for a little more low end
bass.  So I set out today to make this mod, and I ran into a problem. 
  First of all my receiver and bose system are connected with the
factory wires, it just uses some kind of a connector to make it work.  I
tried today to add my amp, comming off of one of the two sets of RCA out
cables from my reciever.  
  To make the rest of my life easier I connected the constant power from
my amp to the "Brake Lights" fuse, in the box under the steering wheel.
I then connected the amp remote to the back of the receiver remote on
lead, and then grounded the amp to a screw under the rear seat.  
  Anyway, I have power to my amp, but as soon as I connect the RCA, my
amp goes into safe mode and won't work.  
  The only thing I can think of is....
       the Bose system won't let me make this connection, or....
       I can't have both normal speaker wires connected from my receiver
and the RCAs.
   Has anyone succesfully made an amp work to their system?  and how?

Jeremy Brandow
'98 Jetta GLX VR6 red, w/black leather
Stock, ....for now