This can be done using the Eco features of your Samsung television.
With your remote, press:
Menu > Picture > Eco Solution > [Enter] and you'll see the option called "Energy Saving". Toggle that to OFF.
Does that help?
I have a Samsung PN50C8000 and like to listen to Pandora. I'd like to mute the screen to eliminate the visual distraction. Can it be done? My audio is a Bose Cinemate II driven by the optical output from the TV. (I also have a Samsung BD-C5900 if there is an option through it.) Thanks.