I wonder if I can reproduce it
Well, here is what fails (pretty consistently) for me.
1. "Start" the car
2. Once booted, activate the rear camera via Honda Hack (in my case, it is mapped to down arrow on steering wheel).
3. Shift into reverse (foot on brake for safety). Camera image changes a little.
Note: Do NOT deactivate the rear view commanded by Honda Hack prior to step 3.
4. Shift back to Park
5. Repeat step 3 & 4 a few times if necessary
At this point, the head unit is either frozen or black (I have seen both conditions). There is no way out that I could find. The 'return' button, the home button, any button just seeks to beep 3 times and nothing happens. Occasionally, there is a glimpse of the home screen when you press a button but it is fleeting.
You may need to cycle between "R" and "P" a few times. I think the problem stems from having the HH rear view activated while shifting gears between "P" and "R". If you turn off the HH rear view prior to cycling between "P" and "R", I think it may be OK.