I think it is do to the lighting, but I have been struggling with the IR on the rMBP. I had IR all day long up until the time of my appointment at the apple store. I even checked in the car before going in to the store that it still was there after the short drive to the store. Once I got in to the store I was directed to sit at a stool and that I could take my laptop out. I did, and in the stores lighting I could not see IR for the life of me. The tech ran a IR test and it just would not show. So whats the deal. Already just from getting back from the store and typing this very message I an see the white box and icons on the desktop when I switch to a full screen sublime editor. And I know it is only going to get worse. Why would I have it so bad here but not at the store? Is the store too bright? Or do they have some sort of IR inhibitor? Yes that last one was a joke... Also, the test that they used was a white and black checkered board, and then black screen. The IR issue I have shows badly, very badly on grey after a white black test.