It’s so hard to understand the words to The Kingsmen’s famous version of “Louie Louie” that kids used to make up their own lyrics and pass them around in notes. So many parents started reporting it for being obscene that J. Edgar Hoover had it investigated. The FBI spent over 2.5 years playing the song backwards, forwards, and at different speeds, but they had to give up because the words were ‘indecipherable at any speed.’ Source Source 2 Source 3