It's becoming a pest!

The following video shows a 'special feature' of the volume drawer for "Audio 1".
My intention:
- simply add a volume fade-out to the highlighted clip.
The result:
- 1. the fade-out button does not work as expected.
Workaround intention:
- I move the timeline indicator to the last frame of the highlighted clip (outside the covered screen area) and
- Then move the volume drawer to the desired value (which in this example is "0")
The result:
- The volume of the highlighted clip remains unaffected, but:
- The volume of the NEXT clip (!) is reduced to zero.

Nota bene: My original desire was to fade the volume from "50" to about "20", so the sound levels of the 2 clips would approximately fit together, I chose to show the effect for a fade from "50" to "0" just for clearer appearance.