This kind of blows me away. but there's actually science behind why sometimes the best way to fix your electronics is by giving them a good whack!
I love that they call it "percussive maintenance;" a sophisticated term for shaking, smacking, or pounding something to make it work. And it works especially well for products that have batteries or older electronics that have parts that might've become out of sync.
But don't forget, don't smack it too hard, you could really mess it up.
And remember, it is a temporary fix at best . . . when a device is at the "percussive maintenance" stage, it probably needs fixing. Don't forget to see if it's the batteries too!