What most people don't know is that Jones and Jackson actually left a mistake on the song that is completely obvious.  

Jackson who died last Friday insisted that the mistake be left in the track and during the past few years sellers of serious music gear have been using the mistake to demonstrate high end music systems.

The mistake can be found on the King of Pop's multi-platinum album "Thriller," and the 1983 No. 1 song "Beat it."

All you have to do is listen to  "Beat It" and at the 2:45 minute mark on the track, which is just prior to Van Halen's guitar solo. The mistake, an audible knock on the studio door, was made by a technician who didn't realidse he was interrupting a recording session.

The mistake was left in the final mix of the song and the rest, as they say, is music history.