I had a TV set some years (actually decades) back with an "instant on" feature that used a small diode across the On/Off switch to let half wave power bypass the switch to keep the tube filaments "warm."
On four or five occasions, the TV mysteriously "turned itself on" and couldn't be turned off, because an insignificant transient on the power line "burnt out" the diode causing it to fail to a short circuit.
When I finally managed to get a circuit diagram (extortion, threats, and very rude behavior required) from the manufacturer that allowed even a minimal look at what was needed, simple replacement of the diode they used with one with adequate current and PRV specs ($0.97 from Radio Shack instead of the $28.15** for the "specified part" from the manufacturer) completely solved the problem.
** The seller offered to fix it, but wanted part cost+markup plus $50 "labor" charge. (Replacement did require $0.03 worth of solder that they didn't itemize separately.)
Maybe that's when I began to be a real cynic about commercial products "Made to Sell" with no consideration about being "Made to Use."