David Letterman said, at that point, he told Quentin Tarantino to hang on so he could get his producer on the other line. Dave said he didn’t want anyone to think he was making it up. At that point, according to Letterman’s story, QT continued his rant:
Article source: https://www.cinemablend.com/news/2489899/david-letterman-recalls-quentin-tarantino-threatening-to-kill-him-over-a-dating-joke