Android 9 brought a lot of new features to our devices but in the same time, it brought an annoying drawback: The volume buttons control the media volume all the time and we have to perform multiple steps to change the ringtone and notification volume.
There is now a fix to this problem and it is called Volfix.
When Volfix is enabled, the volume buttons of your device will control the ringtone and notification volume by default. It will control the media volume while you are listening to any kind of sounds and it will control the "in call" volume while there is an ongoing call.
Volfix requires to be enabled as an accessibility service in order to listen for volume button press events and to map the buttons to control the ring and notification volume instead of media volume.
Please note that at the moment Volfix only works while the screen is on.