Try DVD or other video sources. As to the cable, I'm using the sub ten buck HDMI cables. HDMI cables are a fantastic up sale. (hint: lots of money to be made on cables.)
I am a proud owner of the Samsung LN46A850S1F the TV image is amazing, but after two days I noticed that when the TV screen goes all white/grey after commercials I can see white blurred spots on the corners and middle of the screen; sometimes I can even see the external black square of the DTV channels (HD channel that they do not cover the entire screen). Should I be concerned about this issue?
Also the BB sales person told me that I could be the HDMI cable. I spent $99 on a Rocket Fish HDMI certified 120Hz cable, he told me that it could be that my old HDMI cable can not handle the frequency.. The answer so far is NO I still can see these white spots.
My cable provider is Comcast with a DVR Motorola DCT-6416 III.

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