Provide pictures if possible.
P.S. I used to have a remote with a dodgy right shoulder (the bumper button).
It wouldn't click properly, so I had to take it apart, then glue some layered pieces of paper on the bumper's button stick so it would click the button easier.
How do you mean it fell out, though..
Does the other side fall out too? If they aren't the same, it sounds like one's broken off.
Have you had a rough gaming session and tossed the remote? Dropped it? Had something fall on it? (Happens.. ;d )
Also, just to clarify. The shoulder travels, correct? Just doesn't click? The click is from the button underneath the shoulder that's being pressed.
These buttons, specifically.. http://thumbs.ebaystatic.com/images/g/kM...