I have the Bose system on my '93 Touring and the center speaker has started making horrible popping and crackling noises on me. When its not doing that, the sound coming out of it alternates between very distorted and muffled to no sound at all. I tried replacing the center speaker amplifier with another used one and also replaced the radio ground wire at the same time, but it didn't fix the problem. Any other ideas what might be causing this? FYI the rest of the sound system is original and all the other speakers seem to work normally.

On a related note, if I end up needing a new head unit, are there any factory Mazda head units from newer model Mazdas that are compatible with the bose system? I'm something of a stock junkie...

 

have you taken out the center speaker grill and checked out the speaker itself. Its pretty easy to pop the grill out with a scewdriver. Those amps fail like crazy mine is dead too. I been doing a lot of investigation on these amps. They just fail check out my other post if you want way too much info on the amps. according to the wiring diagram the center speaker takes its inputs from the left and right front channel. Which basically means if you input signal was bad from the head unit then you would have nasty sounds coming from at least one of the door speakers. I suspect you have one of three problems. Speaker is blown, amps you have are both no good. Input power or signal wiring to the amps is no good. My experience with these POS amps is that you probably have two bad amps.

 

the problem is that the stock center speaker is cheap and uses a paper cone and it probably needs to be replaced. When mine started doing that, I took the old one out and threw it away