We had the same problem. In our case it was a loose contact on the plug. After cutting off the old plug and fitting a new one, it runs like new again.

Too bad, fortunately we don't have the problem either. It does seem to be a contact problem. There are more and more electronic parts in appliances that (in my view, even deliberately) define an expiry date far too early. Idea, ask a friend who is familiar with electronics and circuits.

We are not familiar with this problem. Possibly a wobble contact on the switch-on button?