I have been having a problem with the plasma screen not coming on when we turn the plasma on. The screen on/off (red/green) light flashes red. We have made sure that the plug was grounded. Is there something wrong that I should know about. We had intermittent problems the first 3 years. Then it has continued to get worse. We don't want to buy another Plasma if this is a common problem. IT seems to be from the blogs that I have been reading. Any advice.