I'm sorry to hear this! Are you able to see these dots appear on multiple sources? If so the unit may require service. Here’s the thread where you can get details on setting that up: http://forums.cnet.com/7723-13973_102-542437/service-issues-click-here-for-help/
Regards,
HD Tech
My tv screen shows some kind of grid of dots(no not pixels, much larger) in darker areas when playing games. I know it's the TV because even when the image is in motion the dots stay in place.

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