Your vid does not show much except not my style.
I would suggest block plug hole. Turn off water. And then take it apart, could just need a clean out, depends on water hardness etc, but by taking it apart, you will find your answer, even take bits to a local plumber merchants or go down to B+Q or something. Might just need a new seal or something. Do not think it is something very serious. BUT by taking it apart you will find out. From what you say you cannot use it, so nothing to loose, except small bits falling out, which is why I said block the plug hole.
SD
January 2013
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