POCO X3 Pro occasionally makes a sound

I have my phone for two years, mainly used as a gaming phone since it was all I can afford for its specs. Few weeks ago, it started to play a camera-noise, like when your taking a photo but without the shutter noise. It just randomly plays it when I'm either charging it or its just laying around. I tried to open the phone to see if there is any notifications that may caused the noise but no alerts recorded. Anyone knows what caused this? I can't reset this cause this also have files from work and I also use it to login to my workspace (DUO app)