Hi
I have a weird speaker problem. These are the speakers of a mini
stereo system.

The speakers are kind of old. We are talking 10+ years.

Generally they work fine. But if I somehow touch/move the table where
they are resting, they turn off. Nothing I do (shake, move, vibrate)
wil make them turn back on.
But if I just turn up the volume, eventually they come back to life. I
can lower the volume back to its former level and they continue
working normally like nothing happened.

What could it be? Other than that, the speakers sound fine. I thought
about a loose/broken wire somewhere but I do not see how turning up
the volume would fix it in such a way that lowering back the volume
does not "unfix" it.

It seems too weird even for google.