Holding ALT+TAB will activate the flip 2D to switch from a window to another. The problem is that this function remains active for a very short time and I'm not able to select the window I want in the foreground. I also noticed that when I put the cursor on an icon on the taskbar, the live preview thumbnail disappears quickly. With a safe mode restart the problem is no longer there, all is fine! With a clean install of Windows 8.1(no driver and applications installed) the problem is here again; obviously disappears with a safe mode restart also in this situation. What's the problem? A Windows process or service?