What is the sound in Windows 8.1 when the user enters or leaves the laptop?

Question

Windows

Good evening everyone!
After installing Windows 8.1 on the Lenovo IdeaPad G780 laptop, I began to observe an interesting thing - when approaching the laptop (the user approached and sat down or got up and left), a beep sounds similar to the one that sounds when the device is connected and disconnected. It is not necessary to touch the computer itself. User login is standard (regular password, Live account).
The system is installed clean + native drivers from the manufacturer's website. There is no third party software. Among the software from Lenovo, I did not notice anything with similar functionality.
The question actually follows from this - is this a function or is something else going on? Google and other search engines did not give an answer.

Answer 1

Being the one is just like being in love. No one can tell you in love, you just know it. (c)

Answer 2

It's most likely a wire that's stuck.
Try moving it somewhere.

Answer 3

Oh, I'm not the only one! It also seems to me that my Windows is watching me. I work on Linux most of the time, but if I'm on Windows, then I get the impression that when I move in front of the laptop, it does not fall asleep. As soon as I move away, he falls asleep in a couple of minutes. I did not find any such settings.

Answer 4

Windows eight, laptop is also lenovo, though the model is different - I don’t observe anything like that.

Answer 5

Bluetooth headset/phone in pockets maybe?