How can I set audio output both on speakers and headphones to mono instead of stereo ?
Maybe, this might help you…
So Mono audio accessibility is not integrated with Plasma desktop, those commands are hard to type and to use especially by old people suffering from ears dysfunction/disability and who needs this functionality.
No, it isn’t. Actually Plasma is dependent on what sound profiles the soundserver (pulseaudio, pipewire) is configured to. And IIRC it relies what your sound hardware is reporting, by default.
I do agree, tho. It should be easily configurable with a GUI switch, whether it’s for Plasma or DE indedendent