To enter this menu option, select the icon while on the Home Page or press the [MENU] button on the remote control when in television mode, then go to Settings > Device Preferences > Sound.
In this menu you can adjust the various sound settings of your television. Adjustments are possible in the User mode only as this will allow you to change the sound settings to your personal preference. These settings are saved automatically. In other modes, the set will default to the predetermined levels if adjusted.