This seems to be an A20 issue. I wear a Bose Proflight 2 and have literally NEVER had a problem with it in the five years with that I've used it. Not once. Meanwhile, I've flown with quite a few FO's who use the A-20 who've had plug issues. I've told them that I've heard that Bose will swap out the plug for one that works properly, but clearly that's second-hand information. It's not a Bose thing, but rather a thing with the plug they chose to use on the A-20 - Proflight 2 not ever having issues.