TV is over 2 years old. Worked fine up until tonight. Turned on TV, screen is black, no audio, red power light is flashing. First time long then 7 short, then off for a longer time, then 7 short again and so forth. Cannot turn TV using the remote. Must use power button on TV to shut off. I tried turning off and on, unplugging everything and unplugging and replugging the HDMI cords, etc. and restarting over and over. No luck. Please help me! Thanks