Since I can't learn all models and menus I just flip to the manual pages that mention reset. That's what I find to get sets back to normal.
I have a Samsung PN51E550 smart TV. Somehow, when the remote was stuck between the couch cushions, the 3D setting have gotten screwed up. The TV keeps defaulting to 3D, every couple of minutes it switches to 3D mode. When I press the 3D button to change it back to 3D, there's a thin black vertical line down the center of the TV. When I got to the Comcast channel guide, the full guide shows up on both sides of the line.
I'd think something just got screwed up with the setting but I can't figure out what. Thanks-

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