I've had issues with the Logic 7 system and a fried BM54. I repaired the bm54 with the cheap 2 mini amp patch. Worked for a bit but had a ground buzz. Then it died as did the screen. So preparing for the Android head unit install I wanted to retain the logic 7 amps but had no idea if they were part of the problem or not. So in the mean time I was introduced to CorrosionX. The pins on the amps were quite coated. Used the usual contact cleaner and a brass brush. Not much change. Then I used the CorrosionX and the brush. Almost clean copper pins.
Then I repaired the bm54 broken solder joints and put it all back together. All sounds good again. I've missed the full sound. So now the new Android can be plug and play.