umm... wrong thread section?
I was playing Beethoven Pathetique sonata, and went into the wrong key in the recap, the bit where the hands cross. That was very embarassing, becasue I tried to modulate into the correct key...and failed, it ended up totally bitonal, and my memory totally failed me. I finally managed to get back on track.
Not necessarily a performance moment, but the benches can make sounds or if the bench is leather and you wear a belt (I had one that did this) or your shoe hits the bench just the right way, it makes a particular sound. Then you may need to focus on repeating that same sound so the audience knows that is was the bench or your shoe and not something else. It's the accidental environment sound that must be repeat so it doesn't turn into an embarassing moment. "That was the bench! The bench made that sound. Not me!" Of course it may not matter whether the sound was actually produced by the bench or not. It's mere presence makes it embarassing.