I am having a problem changing the screen brightness on my R5. I can navigate to the setting and change the brightness, say from 3 to 5, and then "save" it, and returning to the screen, the brightness has changed, but returns to level 3 after my next shot. I can not lock the setting to 5. (I also have an R6, and that doesn't have the same problem i.e I can lock the brightness setting.)