Was Beethoven’s Metronome Wrong? (blogs.smithsonianmag.com)

I can't find a reference online, but one of the tape decks used for Miles Davis' Kind of Blue ran too slow for one track resulting in decades of people wondering how they tuned flat, including pianos

First hit has 1/2 sentence on this

https://www.google.com/search?q=miles+davis+kind+of+blue+out...