I’ve been using Spacedesk for well over a year with on and off success. But since using the USB On option the connection has been much more stable until a recent update which now places a second screen on top of the proper Extended screen. In other words as soon as I connect my tablet, my display shows the proper screen but only for a fraction of a second and then another screen jumps on top of it and it is black, with nothing but the menu button shown.