My Samsung LCD TV is flickering and I dont know how to fix it.?

I have a Samsung LCD TV and it has been having this flickering problem more and more frequently. I have searched for answers but most questions have this problem when the TV is connected to a lasting cause. My TV is flickering all for everything, when i change the source it still flickers and when I open the carte it still keeps active. I don't know if it will help but we squander directv and I also use it beside my laptop and xbox 360 and ps3.