I’ve personally only experienced this while programming the G6/G7 modes, and one customer reported the same behaviour. I’ve since read several reports of the same sort of thing, though in most cases it’s a fleeting issue that can’t be reproduced and happens very rarely. TimMc referred to this as “switch bounce” and documented both an SC64c LE and SC64w HI with the issue here. I’ve only encountered it the one time while handling hundreds of Zebralights, but it was on a recent production LE.