My Windows 10 desktop has similar issues. It'll fail to lock when idle most of the time. My theory is the mouse is kept active by minute vibrations from a near

My Windows 10 desktop has similar issues. It'll fail to lock when idle most of the time. My theory is the mouse is kept active by minute vibrations from a nearby fan among other sources, but I haven't tested it yet. Either way, how Microsoft's idle detection code can be so poor give the implications is breathtaking.