Samsung bad reception ?

Hi guy's, maybe some of you that are familiar with plasma tv's might be able to give me some info on this...

Basically I purchased a SAMSUNG 50" 4 SERIES HD READY PLASMA about 3 days ago. So the "problem" is I was watching a dvd last night and I noticed like vague lines going across the screen while watching the dvd. It's hard to explain but they are like blurry lines going across the width of the screen in certain area's, not all across the screen.

At first I put it down to a bad rip of a dvd but then when the dvd was over I saw it on the dvd channel too. And now that it's to my attention I can see it on the normal tv stations too.

Is this common with Plasma tv's ? Of should I be bringing this Tv back to the store ?

All opinions welcome