I have an RCA Scenium 52" HDTV DLP tv. Model Number HDLP50W151 Serial Number D513CD09F. My picture was working just fine in the morning, then in the afternoon, i turned the tv back on, and the picture was gone. I can hear the channels, I can adjust volume, everything seems fine but the picture is black. My power button in the front keeps blinking blue. I opened the back up to check the lamp... The lamp does turn on, then i hear a humming buzzing noise, picture comes back for only seconds, then the lamp shuts off and the noise goes away. This cycle repeats every couple minutes. I already relpaced the lamp about a year ago. What is the next step in fixing or replacing what could be wrong???