Usually when backing up, it's while the head unit is first booting up. If I go into reverse, the backup cam comes on right away even though the head unit is still booting up... But after a second or two the screen will go blank for 2 seconds and then come back on, does anyone else have this issue? It's quite annoying, a 2 second blank screen when going in reverse is an eternity.

That is because the units will show the backup camera while the system is booting up. When it is done booting up it does some sort of switching of the video signal so they can show you the text that I never pay attention to. I see mine flash sometimes but I don't remember it taking 2 seconds. I will have to pay attention better next time I am backing up.

Yup. Agreed with Eric it does this when putting vehicle in reverse before the head unit loads

A work around (i guess) could be to push the home button first before throwing the vehicle into reverse.