Did you have experience in hearing music volume to low to enough feeling like in situation using high impedance headphones including in-ear-monitoring ?
I have. Specially in most on android devices.
And my SONY Xperia Z1 also has this unthankful function to protect my hearing, yes, very thank you for it. But I can’t understand what music now playing with my high impedance headphones from unthankful Xperia Z1 even it has big bulk.
So I need to flashing a zip file with custom recovery by refer to http://forum.xda-developers.com/showthread.php?t=2476498.
Download a zip file for Xperia Z1 108 stock ROM. In my case, it worked for my Xperia Z1 157.
You can’t see warning dialog anymore after flashing a zip. But, I can’t sense what volume changed.