On a perhaps not straightforwardly related issue, I've additionally been hearing a metallic ping or pling, similar to the sound that the worked in piezo may make if something little and hard fell on it. It's discontinuous - it can go a really long time without making the sound, then, at that point, do it a couple of times inside two or three minutes. I was trusting that was a bug, possibly from CPU over-burden, yet it does it even on an "vacant" fix.
Thanks.