+ when starting playback of a slot move the focus to the corresponding volume fader
- Reset fade-in and fade-out values when creating a new scheme
- Stop a fade-out process and re-set the slot's volume when pressing play again
(the fade-out process just continued after pressing okay when fade-in was set to 0)
- After "fade out and stop" the slot's position wasn't always exactly at position 0
+ Show a confirmation dialog when trying to close/reset a slot that's still playing