Hi, I just thought that I update my first post.
After the newest firmware and disabling Windows 10 fast startup (tnx for the info Apophis3) I seem to have less issues with the keyboard. Now only sometimes the keyboard is not responding (usually when the usb cable is connected) after reboot or startup. I haven't noticed any issues this far when using the keyboard, even the sleep mode seems to work correctly - thank you for corsair team for adding it, it was really annoying to switch on and off the keyboard all the time. So I could say that my initial issue is solved.
So will c how it goes. But this far its working again.