Why might the keys on a newish Logitech Advanced MK540 wireless keyboard (with mouse and USB dongle supplied) suddenly become highly unreliable/ineffective, sometimes for about half an hour, even after switching it off and on, changing batteries, removing and replacing the USB dongle, checking wifi to whole of Windows 11 PC’s area (still showing all 5 indicator levels)? (And there is no microwave working anywhere nearby — I’ve seen this other Super User question as well…)
Sometimes the problem starts gradually, with some keys failing to be registered on screen and subsequently all keys becoming totally ineffective.
The mouse (unrelated make) doesn’t suffer the problem.
Friend suggested it was a Bluetooth problem, but all the documentation and included dongle seem to say it’s a Wi-Fi connection.
My current solution is to move the keyboard into direct line of sight of the PC case (normally about 1.5 metres away with another PC blocking line of sight) and hit any key – which seems to get it to recover and work again when replaced, even without line of sight.
Is it likely to be the result of interference, either blocking or temporarily unsetting the link to the PC?
