First of all, just so you know where I'm coming from, I am no Apple apologist. I have horrible BT issues with my SE and my 2014 GMC Denali OEM car kit, as I had with the iP6 before that. And I had weird BT issues with my iP5 before Apple finally fixed them in updates. So I know Apple has issues that affect many people.
Ok, so, for the record, it's not that I don't believe you are hearing something. I actually have the dreaded SE death rattle. It seems to be coming from the Power Button, but I can only hear it when I take the phone, hold the phone so th top with the Power button is within a few inches of my ear, and vigorously shake it as if it was a can of paint.
Under no circumstances can I hear by setting it down, picking it up, rotating the camera for videos, or anything else that constitutes normal usage. My Seidio Surface case keeps all SE buttons completely exposed, and I have ABOVE-average hearing.....actually had my hearing acuity tested just last year.
Therefore, logic dictates that either you have a defective phone, which can easily replaced for a new one, or you are one of the MANY MR posters who apparently suffer from OCD. Either way, in my opinion this just isn't a real issue, but again.....that's just my opinion.