I can't see the output signals with the scope widget

Hello!

I am using CsoundQT 7 on Void Linux, with the AppImage release.
I wanted to try the scope widget. So i ran the example for that widget, but the scope doesnt seem to display any shape but a straight line.

Is there something needed to be able to see the signal in the widget? Like setting a channel or something? Or what else can be the reason for the widget not showing the signal while running the example provided in CsoundQt?