I have the RNS510 with reverse cam (and rear sensors).
I've noticed if I start the car and put it into reverse quickly (eg reversing out of garage), the camera sometimes doesn't show up on the screen even though I can hear the camera popping out under the VW logo at the back.
It seems it takes a few seconds for the RNS to "boot up" properly and if you dont allow it to, the camera viewing somehow doesn;t kick in. If I were to drive off regardless, the camera still won't transmit until I turn off the car, turn it back on and wait the required few seconds for the RNS to "system start" properly.
Annoying to me but has anyone else noticed this?