Paul, as you probably know this is the display settings. If automatic doesn't do it for you, as this should adjust display accordingly, then you can change the brightness and contrast from current to liking and it should stay adjusted. Try it, nothing to lose!
Center Display
Adjusts the display brightness, contrast, and more.
Function Available setting changes
Display Off
Turns off the display while still providing audio content. ―
Day/Night Mode
Selects the center display brightness mode.
Automatic,
Day,
Night
Brightness
Adjusts the brightness of the center display.
Brightness
(11 levels)
Contrast
Adjusts the contrast of the center display.
Contrast
(11 levels)
Show Drive Results at Ignition Off
Provides energy efficiency results at the end of the drive.
Enable,
Disable
Home Screen Clock
Selects the clock style displayed on the Home screen.
Analog,
Digital
Ambient Display
Enables a simplified interface accessible from the Home screen.
Blank,
Clock
Restore Factory Settings
Restores the display to the original factory settings. ―
Alan