I can confirm this. Especially on level 1 (the so-called idle mode) it is particularly annoying. In the meantime, I have placed some felt glue and it has improved somewhat. By the way, at level 4 it's not the casing that vibrates, but the whole device...

Fortunately, I don't have that. In my opinion, however, this is not a guarantee case - there are sometimes constellations where vibrations build up and then a so-called resonance vibration occurs. With a tap on the unit (not recommended), you could break this cycle. I would try to place the unit in a different position (for example, on a piece of carpet) and make sure that all the parts are properly seated. Good luck.