One of my managers at work says that everything electrical and electronic requires blue smoke in order to operate correctly. He might be right. Have you noticed how when the blue smoke comes out of your laptop the laptop doesn't work any more? Or when the smoke comes out of your vacuum cleaner it also stops working?
I had a similar demonstration of this theory today. The GFCI/ELCB socket in my downstairs toilet let it's smoke out today. Good job we caught it too otherwise we may not have had a home to live in.
Turns out that there was a loose connection in the return wire. Every time my wife ran her hair dryer it would cause the wires to move under the stress of the current load. The return (a white wire here in the US) would then disconnect itself then reconnect itself causing lots of sparks and arcing and burning. The result was that both the wires and the socket would get hot and so release their smoke.
Good job we caught it. Or rather my dog Rascal caught it. He heard the GFCI arcing then ran into the toilet and started scratching at the wall. It was only when he started barking drawing me into the room that I saw the problem. GOOD DOG!!!!! Extra belly rubs for you.