Hitachi 32pd3000E plasma - power problem?

i have a problem with my plasma bought 4 years ago. There seems to be a problem with power. It first happened after a power cut, the TV switches it self on and off repeatedly. This seemed to rectify itself after being left for a number of weeks (new tv had to be purchased), but recently it's done it again, sound lost first then switching on and off. Is this a problem with these TV's