Ok, now i have the same problem with VLC.
But i know why!
If you have any Program running which is set as "Always on Top" iCUE does not detect any other program running which has the focus.
If you only have one Monitor this is normal as you would not use multiple programs in the Foreground. But if you have, like i have, two monitors this produces a problem:
You have one Monitor with one program you are using and another monitor with a program which is always on top but you are not actively using this program.
Despite you are using another program iCUE does not detect the program you are using but the program which is set to be always on top.
Thanks for all your help. Now i know to circumvent this problem.
PS: Another "Gaming Software" did not had this problem. Used it long time with my old Keyboard. So there exists a solution for this problem so Corsair could fix it.