Can't adjust volume in off screen when "change tracks by long volume press" enabled

[Jihe Wang]

I have already used adb to grant a proper permission and is able switch tracks.

But I found that if I try to change the volume by volume keys short press after turning off the screen,the tracks will be switched,but volume did not change.

I use lineage 16.0 with android 9.

I don't know if other systems have the same problem.

Device is Mi 5s Plus.

Poweramp v3-build-853-uni[853009-1e73a2bc] Full version 64 bit