FT86club user extrashaky saves the day, and my eyes.

Driving the BRZ at night, even with the head unit in night mode can still be a blinding affair.  The 'black' background is still backlit and literally takes away your night vision if you are driving in the middle of nowhere.  This is not located in the manual anywhere.

In the thread "Hidden Features" on FT86club.com user extrashaky lays out his amazing finding:

"If you press and hold the "Audio" button, a hidden menu appears that, as far as I know, is not in the manual for the nav unit. If you're in day mode, a "Night" button appears at the top of the screen in that menu. If you're in night mode, that button says "Day" instead. Pressing that button toggles the night/day modes and causes it to ignore the headlights without having to adjust your display to full brightness.

So if you're driving with your headlights on in the rain during the day and want your display at daylight brightness, just press and hold the Audio button and push the "Day" button on the screen."

The best part is you can just turn the display OFF if you want to while your audio still plays!! This is not located in the manual anywhere.  Someone buy this man a beer, or root beer, or whatever he wants.