Playbackspeed/Listeningspeed seems stuck

Goodevening members,

Is there a payed version for this software?
Does anyone know what I am missing?

I cannot alter the playbackspeed/listeningspeed?

Regards,
G.

Anyone ever experienced the same problem?

The playback speed is changed by the slider 1 (in the picture). To start playback with a changed speed, you need to press button 2 (in the picture). Or you can assign any key combination for playback with a changed speed

Much obliged!!