parallel video in presenter console slows main video down

I’m running Mint 19 (Ubuntu Bionic B). The default LbOffice-version (6.0.xx) has serious video rendering problems. After installing the rendering is quite OK, but slowed down due to the parallel rendering in the presenter console. When the presenter console is put into “slides” mode, no video is actually rendering in this console. But I want to use the “notes” mode of the console.
I’d suggest a workaround by means of an option where one can disable the parallel rendering.

By the way: the console rendering exhibits short interruptions at every clock tick instance. Things get far worse when “Rehearse Timings” are activied.