I recently bought an 04 RX8 GT with 50k miles on it and when I drove the car at first nothing was wrong but then I noticed that my front left speaker cut out. I figured a wire might have gotten disconnected or some other issue but then all of a suddon it came back on. After that the front right will cut out or the rear speaker and so on. Sometimes mutiple speakers will cut out at once or just the bass will cut out fully of some or all speakers randomly. Other times the bass will turn up fully without the display saying otherwise and same with the volume. This happens randomly, when I just turn the car on and it idles or if I'm cruising at 80 on the highway after driving for an hour or so. It's quite annoying.

I took my car to a professional car audio shop and they couldn't detect the problem so then I went to a Mazda dealership and they ran a diag and couldn't find anything wrong. (What a waste of $100) The dealership stated it could be the stock Bose amplifier or head unit malfuntioning. I would just like to know what it is that is wrong and if I can fix it or replace what's wrong.

 

https://www.rx8club.com/tech-garage-...repair-201080/

I had the same problem, this helped with mine.

 

i haven't done the fix on mine yet, but the diagnosis is fairly simple.

i looked in the wiring diagram, and the deck has 4 outputs; LF, RF, RR, LR. the front output splits, the tweeter gets signal right from the deck, and the door speaker has an amp.

so since the LF has one output from the deck/audio unit, and the tweeter works, that means the audio unit works, and the problem must be the amp or the speaker. mine is intermittent, and therefore most likely the amp.

that there is a fix for the amp is really neat!