[walfreyydo]

Maybe I am mistaken but the driveshaft should not spin at all with the clutch pedal released (assuming that no one has their foot on the clutch when you took the video). The driveshaft splines should be engaged with the clutch disc and flywheel and the shaft should not move, not even a little.

Since there is movement in the driveshaft, it leads me to think the rubber center on your clutch has disintegrated, allowing that movement of the driveshaft which normally shouldnt be there, and also likely the sound of the "catches" on the clutch disc hitting (a failsafe built into the clutch disc if the rubber center fails).

Seems like a clutch job is in order (and while you are in there rear main seal). I would deal with the clutch first and then see if the sound persists. Make sure you get a Sachs clutch without the rubber center.