Tell more about the age. For your research, google BAD CAPS and then SAMSUNG BAD CAPS. The symptom is too close to the bad caps plague (not a Samsung exclusive issue you will discover) and one that on some models Samsung offers an one time fix. Be sure to keep calm, call it in and if they don't offer the one time deal, post the transaction number along with the missing detail.
My LN40A550P3F Samsung TV won't turn on when I want it to. But then randomly 5-10min later it pops on. The TV then will not stay on and does that opening up 'theme' music many times. how do I fix this?