I've just added one of those dash cam/sat nav/android mirror devices and instead of using the rubber bands supplied for fitting, I stripped down the rear view mirror and mounted the new device to the carcass of the rear view mirror. I have the auto dim rear view mirror so disconnected the wires, built everything back up and went for a drive. Central locking stopped working, so I reconnected the wires in the mirror and working again, just a heads up that the sensor for the key fob is in the rear view mirror if charging is not the issue for others reading this thread looking for reasons their fobs stopped working.
Might post up some pics on new thread of how the mirror looks in case someone else fancies fitting same.