I'm sorry to hear that you're having this issue.
Unfortunately, I'm not able to offer any diagnosis for that symptom. I'd recommend having the unit inspected by a service technician.
Hello - I have a 50" samsung plasma (model code PN50A510P3FXZA)that is approx 1.5 years old. Occassionally (and becoming more frequent), the entire screen will instantly turn to static and and horrible loud static scream emits from the speakers. The TV cannot be turned off and is nonresponsive during this time. This lasts for 5-10 seconds after which the TV turns off and then turns itself back on. All is generally back to normal after this. The TV hangs from the wall and appears to have adequate air flow all around. Thanks for any ideas !!!