Cubase Pro 10.5 not compatible with 3 screen setup?


I have just installed Cubase Pro 10.5.20 on my new Computer.
Im running 3 screens on a Nvidea RTX 2080 card. The 3 screens act as one big screen 5760x1080 with Nvidea Surround enabled.

When I start up Cubase 10.5 everything is fine.
It starts up maximizing the top menu bare over the 3 screens.
The acual project is also on 3 screens and I can pull the project from one screen to the other.

However if I try to move the top bar in Cubase ( with the menu screen) in order only to have cubase on one screen, the whole Cubase starts flicker ( blink) and Cubase locks completely. Only way to get out is to press ctrl-alt-delete.

Is Cubase not compatible with 3 screen setup??
Is there a setting in cubase I should apply?

Can anyone help?

Best regards

I think you might increase your chances of getting a good answer if you publish this question in the Cubase forum instead.