Dremel 4000 - FAIL

A short video showing how my Dremel 400 has failed with a constant start-stop-start-stop symptom, and a quick look inside at the circuit board which controls the speed of the motor.
What's gone wrong?

[@shovington67]

That would make a great movie prop in a comedy film! Its actually a funny noise and movement, as if its alive and has its own character.

[@darren-garden]

I have one with the same fault, but with a longer period between pulses.