So mine had a fun issue, it rattled at first, then it started throwing massive amounts of high pitched noise into my ear when on noise cancellation or transparency. It was horrible. I got them replaced, hope to whatever higher power that it doesn't happen again. But if it does, then I guess I'm out entirely on Airpods, time to switch to a different brand for wireless audio.
Oh yeah, and even when I was on the phone going through troubleshooting with Apple they had me reset it and even only a few seconds of the high pitched noise during troubleshooting was unbearable to my ear, let's hope for other people it doesn't ever get that bad cause it could damage people's hearing.