What is this strange phenomenon with the switch? (see details)

Same thing happened with a switch in our kitchen , we had to call a sparky he had to replace the switch . It was all black inside from the sparks , he said we were lucky not to have been shocked or worse .

My advice: stop touching the switch from now on and call for a pro or someone you know who has experience in the electricity-field.
It could have been drama (like sandy’s sparky stated) if you got shocked.
I got shocked once when in my brother’s house.
I flipped the switch to turn on the hallway-lighting and i found myself ‘flying’ five feet backwards.
My arm was numb/heavy for two days.
So, be careful, dawg.

That’s a common occurrence with switches when they get old. In the best case, the contacts wear to the point that they don’t “snap together” the way they used to, and you get a little bit of arcing before they close.

In the worst case, they’ll continue to arc some time when you’re not watching it, starting a smoldering fire in the wall, which will burn down your studio when you least expect it.

I’d go ahead and have that switch replaced before worse happens.

Damn, I was afraid it was bad.

Thanks for the responses all Lurve.

I do not feel like getting a jolt and am taping the switch off and will call an electrician.

I will have to shut the circuit off on the studio till one can visit. (Why do these things happen on holiday weekends?)

@grumpyfish Thank you for letting me know that it is caused by wear. That makes sense as I use it multiple times a day.