[itsme]

Thank you for your assistance. Both hints were helpful: scrolling with the mouse wheel does the job and I learned how to use the scroll feature of the touch pad like the mouse wheel. And arrow up / arrow down also work correctly as soon as the focus is set on the list.
I was (and often still am) confused by the fact that a single click or tap on the list opens a song instead of just setting the focus.
I have to get used to that.