New D55-E0 screen sometimes flashes black with white lines and areas

Two-week old Vizio D55-E0 has started to do this thing where the screen will flash black but with white lines and white areas (squares or rectangles). The flashes are fast, like a fraction of a second, and intermittent and random, sometimes hours between them and other times two or three a few seconds apart. The lines and areas do not occur in the same places or in the same amount each time. The TV does it regardless of input source, and I have seen it on top of the TV menu. It did it once during power on before there was any video input at all.

I haven't seen any reference to this particular behavior. Other descriptions of lines or screen flickering are of constant or periodic events, which this isn't. Did I just get a lemon?