Since brand new a few months ago the screen will flash a black screen for about a half a second. sometimes it will do it several times in 10 seconds, sometimes it may not do it for 30 minutes. It does it when watching with a tivo roamio and also with a blu-ray player. Would it be the refresh rate of the tivo not matching the rate of the tv? Samsung already replaced a part and the screen still does it. What gives?