Just do it, it is easy, and if its not working, youve got nothing to lose.
No, they came from the MoBo, because I didnt use a cardboard box, but some ceramic thingys, and I heard the same crackling. It worked at the end, but it was weird.
Did you check that the flat cable going from the mobo to the touch panel didnt get damaged? or maybe is just not well connected to it. If it doesnt do anything, it can be a power-on touch button problem, instead of something more complex.