I finally found the hidden solution to controlling the Sony touchscreen stereo in my 2023 Winnebago. This should be helpful to any of you with the Sony XAV-AX8000 or AX8100 models who have been struggling in vain to turn off that highly annoying and unsafe-for-driving demo mode or to adjust the clock.
1. Most of the touchscreen is
not scrollable. But the bottom ~25% strip of the "Home" screen displaying icons for the different audio sources
*is* scrollable from right to left. (see photos below) Thanks a lot, Sony!
2. Swipe left on the icon strip at the bottom of the "Home" screen to reveal a secondary home screen. You will see the "Settings" option in the secondary Home screen.
3. Within the "Settings" menu, select the "General" option.
4. Inside the "General" submenu, you will find the options to change the Language, turn the Demo mode off or on, set the Date/Time, adjust the Beep, and adjust the Rear View Camera.