Samsung ina650 question- stutturing smoke/clouds

I have searched far and wide for someone describing the issue that I have.
I only watch 1080i cable input. I notice in a scene with smoke or background clouds that move across the sky, or if I stare at the "background" of a scene that isnt moving, the pictures stutters or breathes. The clouds will move across the screen in a jerky motion. the amp can be off, low or high and doesnt seem to effect this at all.
Is this normal, anything in settings to get rid of this? its not a big deal, but now that i know its there I ALWAYS see it in everythng I watch.
Also in a fast moving action scene like in transformers for instance things get a little blocky sometimes.

Is this normal for all LCDs? is it my HD source (uverse)
I dont have a bluray to compare.