I have a difficult car to install my F90BT in and could not do it myself due to all the impacts - the venting issues, custom dash mounts, etc. So I had my install done by a very reputable shop. Standing completely still (0 mph - not 1Omph), when I disengage the parking brake, all the cool icons go grey and I can no longer watch videos. I assume this means the parking brake was not grounded the way it needs to be for this mod to work, which, as I see it, means the installation was done completely by the book.
I do not want to mess with the install in any way - that means no pulling the HU