Has anyone had problems with this panel "flashing"? Mine has been flashing black screens in between displaying content, and it only seems to be getting worse. This happens on any HDMI input (haven't tried anything else), and nothing that I have tried seems to make any difference. I have tried the hard reset (plugging in power while holding the power button) but it doesn't seem to do anything. I guess my next call is to Sharp? It is still under warranty but replacing a 90" panel is going to be a pain, to say the least. Anyway--if anyone has a similar experience, please let me know.