Sometimes I fall asleep with my Lumia 950 XL in hand and if I happen to roll on top of it, the phone beeps me awake. (This only ever happened twice.) It uses a completely unique audio cue, lower (that is to say; deeper) and shorter than normal notification chimes. A single tone. Does not repeat or get louder, but nor does it respect volume sliders/quiet hours settings, interestingly enough.
Very similar behavior to what old keyboards/computers did when we held down a lot of keys at once. Except the sound -- that was a constant high pitched "beep - beep - beep..." and this is a single dialtone-like "bap" and very short.
This undocumented feature is really useful as I don't want to crack my screen or break my phone in half by sleeping on top of it carelessly. Can anyone even reproduce this strange behavior? Is it configurable? Or am I hallucinating? No matter how much I press the phone with my palm, it does not beep. Only when I fall asleep on it.
Bonus afterthought: not sure if the screen timing out by itself matters or not.
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