RT 2010 Screen mechanism problem

[pdes]

The screen on my 2010 RT is behaving a little erretically. Under normal operation, when it goes fully down, it hits the bump stops then springs bak slightly to give a small clearance. However, I have just noticed that it is now not going all the way down but stops with about an inch clearance. It goes back up OK and otherwise works normally. It seems also that if I turn off the ignition and turn it back on, the problem clears for a short while then returns.

 

What governs this behaviour? Is there something I can adjust?

 

Thanks