recent software update

i have just updated with the tomtom home, my fathers tomtom one. but now, the contrast is terrible and it is sometimes hard to read the screen comfortably in even slight daylight.
also there is a stupid faded type effect in the middle of the screen when in the menus. does anyone know how to adjust the contrast and also if that faded effect can be removed?
the version shows 6.560

please someone help, any answers appreciated.