New Speakers problem
 

OK so I just bought a 2001 s4 and the speakers wernt working, I said no problem. Well Ive spent hours on this and cant for the life of me figure out what is wrong. I got the rear speakers working but the fronts are still not functional. Ive checked all the wiring. I looked for a stock amp in the car but cant seem to find one and the way it looks the wireing for the doors go straight to the stock Headunit. Its the symphony stereo. If anyone has any idea what might be going on any info would be greatly appreciated.