I love mine too!
Have found that the vibration of the machine can rotate the flame out of the critical position, or even cause the whole burner to "walk away" so that you lose the critical flame positioning where the blue part of the flame is getting sucked in, which Jim's video so well shows. Magnets have been found to be useful in helping to keep the burner where it belongs, while still allowing for adjustability to optimize flame position.
I have a newer one and it has a magnet (stick on) on the base to keep the burner in position. Of course, it won't work with that nice copper burner.