Have anyone noticed, after you adjust volume of computer the loudness decreases for few minutes.
for example, I am playing music at 24% volume, and when I change system volume and change back to 24% again, the loudness of music decreases for few minutes. I thought my ear was wrong so I tested with app to measure the decibles. I figured I was getting 50db sound at 24% and later when I changed back to 24% I got 30db of volume for few minutes but it eventually rises to 50db.

What is reason for such behaviour and how to fix it?