It may be this turns out to be an unresolvable issue.I suspect something is wrong with this KDK
But, I still have a couple of thoughts.
Since you have two systems, one with the issue and one without, what do you see in the console log immediately after launching Parallels? Any errors or different entries on the MBP than the iMac?
If nothing obviously different after launching Parallels, any difference in the logs after launching your VM?
Finally, since according to Parallels they depend on the Mac OS for the video switching setting, I wonder what would happen if you set the MBP to use the discrete video card only before launching Parallels?
I wonder if this might help?
How to force your MacBook Pro to use its discrete graphics card when…
The solution is to use the machine’s discrete graphics card instead.Because the discrete GPU uses more energy, I don’t want to use it when I’m on battery…
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