System: .121 Android 10 with January 2020 security patch
Phone does recognize the headphones, shows the icon, but there is no sound in them. Speakers are working just fine.
Restarting the phone does not work. Unplugging headphones and plugging in does not work. Checked different headphones. Checked different players. With no results.
Only way to have sound in headphones is to play the music on speakers first, then plug in the headphones, but even that not always works.
The issue might be with audio wizard, since any change in the sound profile automatically stops the sound output, even though the audio wizard equalizer and music players show that music is still playing.
The solution I found is turning the audio wizard off and then rebooting phone. This way there is headphone sound output without any complication.