I don't understand what you want to do here.
I'll try to explain again:
- So, let's say I'm playing a track from playlist A
- Now, I would like to start playing a random track from playlist B
To do this, I would have to
- Click on playlist B
- Select a random track manually from playlist B (or ctrl+h and then select a track)
- Double click on the track to start playing it
Why can't you just press play?
- The play button controls the currently playing track (from playlist A, in my example)
- So, pressing play just plays/pauses the current playing track
Solution
- A button that shuffles the current selected playlist (not the one that is currently playing) and then plays a track from it.
Behavior when using this modified feature
- I am playing a track from playlist A
- I press play/pause button: the current track plays/pauses
- I click on playlist B
- There is a "Shuffle Play" button between the "Clear Playlist" and "Undo" buttons. I click on "Shuffle Play"
- The playlist B is shuffled and a random track from the playlist B starts playing
Hope this makes it clear. I'm pretty sure many people would like to have such a feature, it is pretty convenient this way.