Report as inappropriate

I've had this happen twice now and I'm fairly convinced it's an issue with the switch not being rated for the current the printer needs. In both cases the switch became stiff and then broke accompanied with a burnt plastic smell. At this point I've bridged the power wires together with an alligator clip and just unplug the printer from the wall when I'm done.

tl;dr I don't know why this happens but it might happen to you again in the future even if you fix it.