I am having the same problem on my MY2012 and a replacement switch has been ordered. Looking at the plastic triangle that needs to be lifted, this doesn't appear to be an entirely obvious task.
From a previous post:
It's trivial. You need to lift the black triangle that holds the switches on the driver's door. To do this, put your hand in the door handle and turn your fingers forward. You will feel that there is a slight indentation to allow you to lift the back of the black triangle. Lift firmly until you hear the first pop. Then slide your fingers in and lift firmly further back. Once you hear the second pop, you can slide the entire assembly toward the rear about one inch to free the front and allow it to lift free. From there, you can see what needs to be done to replace the module, especially once you have the replacement unit in hand.
In my case the quality of the fit is quite good. There is just a horizontal seam where the top piece meets the bottom piece. No obvious indentations or other things to hold on to. It is clear that the top piece must be lifted (presumably after the mirror knob has been removed), but this doesn't appear to be a simple hand job of pressing here and lifting there. Any advice would be greatly appreciated. Thanks.