Just bouncing some ideas around…
Do you have multiple monitors?
If so you could run a copy of DIView on another monitor just to confirm that the input control peripherals are still active when the issue occurs.*
When the issue occurs and you hit ESC is the simulator unable to actually read inputs if you view these in the Control menu?
(For example if you check your joystick axes, do they register in the Control menu or is that not functional also?)
If not working in control menu after 1 hour and DIView also confirms not operating maybe it’s worth checking the power saving behaviour of the USB at Windows level? If left untouched for an hour maybe it’s windows putting them to sleep? Once they go into sleep mode it’s possible the sim might not register inputs from them again until it’s restarted?