I'm using Xperia XA1 for about 4 months. I'll explain what is happening in my phone. For the first one month there was no problem in the sound (during music playback externally and headset), but after one month the maximum sound of the phone reduces the average sound I use mostly that is I usually hear at 10 pts but after one months when I increase the sliders to maximum the sound is just the same. I thought it would be a problem with some app so I did a software reset and checked... The problem is GONE!
Again after one month it occurred and without a doubt it went perfect when I reset again. But now again one month same thing is happening.... I don't know what is this...
PS: I have checked it in safe mode and same problem is there. I used Inbuilt music app, Spotify, Google Play Music and Apple Music. Everything gives me same error!!!!
Thanks for the reply. I turned off the normaliser switch but no change. What do you mean by other sound settings? I even tried turning off clearaudio+ and varied equaliser settings but nothing is affecting the music sound. even xLoud feature to enhance loudness of internal sound is not changing whether on or off.