AKA the Magic Xylophone is a scene from Simpsons S8E14 where a fan nitpicked an error in Itchy & Scratchy where Scratchy’s skeleton ribs produce different tones when struck consecutively.
In episode 2F09, when Itchy plays Scratchy's skeleton like a xylophone, he strikes that same rib twice in succession yet he produces two clearly different tones. I mean, what are we, to believe that this is some sort of a, a magic xylophone or something? Boy, I really hope somebody got fired for that blunder.