Audio Systems: car stereo replacement, plymouth neon, aiwa stereo

Question
I recently bought a used 1996 Plymouth Neon. An aftermarket Aiwa stereo was in the car when I bought it. However, the previous owner told me there was something wrong with it. I don't know whether it ever worked properly, but as of now it only works when the volume is very low and the bass is turned all the way down. The deck still has power, but the speakers quit when the volume or bass are turned up at all. The wiring appears to be correct coming out of the deck, but I have not traced it beyond there. All four speakers work, and they all quit at the same time as if an amp is getting hot or something. I don't really know where to start, so if you have any ideas, I would really appreciate your advice.  Thanks

Answer
Greg,
  
  first go to www.streetdreams.com/wires so you can get a color code and really get into the wiring to make sure the install was done properly .. now if this doenst work out , and you are positive the speakers are functional .. most likly it is the amp on the head unit that is faulty, a simple replacement should do the trick .. hope this helps you out if you need anything else let me know

thanks