Power control board failed after 18 months. A power surge is unlikely, because the TV and all connected components are plugged into surge protected outlets. The coax for a connected set top box is connected to a fiber ONT, so not a source for external surges. The TV has been problematic from a software standpoint from the beginning, requiring repeated setup operations. It fails regularly to operate with its connected Sony receiver which also looses configuration. Don't know what's happened to Sony, but this long time fab is done with them.