I also have this problem with my MacBook Pro (Retina, 13-inch, Early 2013), ipad air 2, and my iphone 6s. It started in my mac with earphones. Then I tested multiple earphones to see if it was just the earphones itself. All 3 have this problem. The to restart the computer and watch youtube on my ipad instead. Suddenly it had the same problem in my ipad with all 3 earphones. I restarted everything and it still wasn't working. Finally, I went to my phone to answer a call with earphones on. It still made the sound! Now on my phone! I took out the earphones and suddenly my phone makes this really loud static sound. Keep in mind my devices make this sound even when there is no earphone plugged in now too! It's almost like a virus that keeps popping into every one of my devices. I know this isn't possible, but it sure feels that way. I can't call, stream videos, or do practically anything that involves sounds now because of this problem. Is there anything I can do to fix it? or is it more like something I would need to bring into the apple store?