So earlier this afternoon the display on my pixel 1 XL suddenly stopped working for no obvious reason. From what I can tell everything else on the phone is working fine, it was on silent when it stopped, but holding the power button will still cause it to vibrate. I took the screen off to check the connection which appears fine. So I'm thinking it is a fault with the screen, after ordering a replacement I put it on charge, when a few hours later it started making a strange noise. The link below is the closest in terms of tone to what was playing, It stooped when I pressed the power button. I've never heard this before so I wonder if it is some sort of diagnosis sound? Any ideas what this could be? thanks.