Screen Adjustments are located in the System menu
Display brightness and audio volume is adjusted in the System menu using the 5-Way Navigation Switch
Press the navigation switch 'Enter' button to enter the menu system
Navigate to the 'System Menu'
Select the 'Volume' bar (turns orange) and raise/lower the volume.
Deselect the 'Volume' bar
Select the screen 'Brightness' bar (turns orange) and raise/lower the screen brightness.
Deselect the screen 'Brightness' bar.