Need help! My picture and sound is great but, my tv is now making a pop noise and turns off the screen and voice. The green power remains on during this problem. I have powered it off with the remove and by hand to turn it back on then it repeats same problem. What is this and how can I fix it? I have also unplugged it and wait for a couple of minutes and it comes back on as if nothing is wrong then after a while it does it again. Help!! Oh and My TV has been hooked up for 7 years and not messed with...