The remote worked for over a year. At the top of my projector screen is an IR "Eye" that transmits the IR back to all other components except for the projector. The IR gets to the projector by bouncing off the screen. Thus double the distance.

This is why I was wondering if emitters get weak.

Well, I programmed another mx-200 (using the same editor file) and it worked from June 7th until 2 days ago. Something is definitely going on. I don't have any trouble with my mx-850.