Since Rekordbox 7 Multiple Monitor issue

Hello,

first what I now describe works perfectly fine in 6.8.x
I have a 4 Monitor/screen setup and it happens also with only 2 or 3 Monitors ON.
When I start Rekordbox 7.x on my choosen Main Monitor, the GUI works as expected.

BUT, when I move The Rekordbox Window (Fullscreen) to any other Screen, the annoying issue starts!
In certain areas (mostly seem to be left and right and the lower section of the screen, the Mousce clicks are not recognized where I click.
Example the Treeview is not reacting and if I click in the playlist the Track can be selected only until the Track Title section but everything right from it, is simply ignored, I can´t access the right Options like info or so.

If I only draw the window to the "Nearly max size and not use the Window max option", it is also weird.
Mouse clicks are not recognized where I click, like I click on Track 15 but RB highlights a Track above, in this example Track 5. I can use and change the Rating as example or rename the Title, but I need to clickthe track 15 below. I can`t access the bottom tracks, because I can´t click (obviously) under the current screen.
Under certain conditions, it works fine on a second Screen (but not always) and sometimes it is not accepting any mouse clicks on another Screen in fullscreen Mode, but when I make it a little smaller in Window mode it works like normal.
That is extemely annoying!

As I said all screens are working perfectly in 6.8.x
But In 7.x it is a Mess!

It is really difficult to describe the issue.