Quicken 2021 running under Parallels 17 Flickering/Jumping - basically unusable

I have been having this issue now for a better part of a year and it is getting progressively worse and worse, now to today where Quicken 2021 is basically unusable.

My Set up:

• MacBook Pro 15", 16 GBs RAM, 3.1GHZ Quad Ram i7, Radeon Pro 560 4 GB Graphic Card running Big Sur 11.6
  
• Parallels 17.1.0 (build 51516) running Windows 10. I have tried both "Automatic" setting (4 CPUs, 6 GB Ram) and others have recommended 2 CPUs and 8 GB RAM)--does make a difference.
• Quicken 2021

My issue is that Quicken flickers and "resizes" it screen footprint, often eliminating the Windows Task Bar, then flickers back when ever you click on it. While it is doing this is also looses it menu task bar (it is there but blank.) Of time when I click on something to edit or type it will go back and forth on these 'resizes" 10-15 times before it will settle down.

The issue is described somewhat in Quicken threads and I have tried:

1. Setting Task Manager to set Quicken to "Always be on Top:
2. Turned off Annimation
3. Resized the Quicken window to not have it fill the entire Window
4. Resized Windows
5. Some say not to have your file in Drop Box so I have tried saving a back up copy outside of Drop Box but it has no affect.

I would add I have been using Quicken since 1993 and do not back up or eliminate data especially since I have investment accounts with long histories. I though cannot imagine this is the issue.

I am open to suggestion on other ways to try and fix this problem.