What is the chime my phone is making?

[BM02GAN]

Randomly and sometimes when I press the power button to unlock my phone plays a chime.

WTF is it and how do I stop it?

 

[Chintan Gohel]

Randomly and sometimes when I press the power button to unlock my phone plays a chime.

WTF is it and how do I stop it?

settings > personalisation > sounds > check if the toggle for lock and unlock is on -switch it off

 

[daimv]

One thing that took me a while to understand was a weird sound that seemed to appear at random times... In the end, I discovered it was the NFC alert sounding when my phone was on top of an id with RFID or something with NFC, check if it isn't the same for you.

 

[RumoredNow]

I agree... NFC is being triggered. The classic symptom is "mystery chimes."