Chosen Solution
I have a mid 2014 15" rMBP. I had a memory fault recently that would cause the machine to reboot when certain addresses were used. I recently purchased a replacement logic board and installed it today. Everything went well, until I tested the audio and I realized that the left speaker was making a popping and hissing noise. A loud one at that. Convinced that I had somehow damaged the speaker in the installation process, I removed the new logic board and reinstalled the old one. The speaker seemed to work fine with the old logic board. I then reinstalled the new logic board only to have the popping and hissing reappear. I tested with headphones to see if it was a problem with the audio chip, but they work fine. I’m at a loss to be honest, having spent a fair few hours installing, reinstalling and reinstalling yet again. I’ve even purchased a new speaker just in case, and am still having the same problem even after swapping it out (If you appreciate one must take the motherboard out to replace the speaker, you can imagine how many times I’ve done this now.) Does anyone have any suggestions? I can find very little anecdotal evidence of this happening to others. Any thoughts would be greatly appreciated.Thanks in advance!
Well I’ve got some bad news ;-{ Your replacement logic board has a problem with its Audio DAC chip logic located near the headphone jack (Cirrus marked chip)
Carefully inspect the area for corrosion or staining. You may need to return the board for another.
