That was my point. The media always blames the PA system or anything they can think of before anything is tested to find the real cause. For example: A man I used to work for serviced school fire alarms as a side business. He was on a call one day and got a shock from a piece of conduit that supplied power to the service outlet next to the alarm cabinet. He took a piece of wire and touched it to the grounded alarm cabinet and the bare metal outlet box and tripped the breaker. They called their maintenance people in to find that it had 120 VAC on it and it was traced to some damage where the conduit had separated, and the insulation was worn off the black wire. There was no green bonding wire in the conduit, so the rest of the run downstream was hot. Multiple factors caused the fault, but it could have killed someone. It turned out that kids were jumping up and grabbing the conduit at a bend and hanging on them to show off, and had finally pulled the screws out of the ceiling that held it in place.