It is unlikely that you have received two displays that are faulty, simply that the bordmonitor needs to be adjusted to bias the electronics correctly to provide a bright clear display with the correct viewing angle. These screens are not individual to each model. They are produced for a variety of LHD and RHD and must be adjusted to suit the vehicle. (normally done on the bordmonitor assembly line)
I have searched high and low without any real success on the internet to find a correct procedure for adjusting the bordmonitor but it seems the manufacturers consider it a state secret.
The only way I have been able to adjust my screen is trial and error. Use a dim environment and adjust the pots one at a time to see the effect while viewing the screen in a mirror.
There is a partial description of how to do this by TEXASPAUL on Bimmerboard.com Adjusting 16x9 BoardMonitor (Very Long)
Good luck, and if you do come up with a decent method, please post it back here.