Just purchased a 50A650 (graduation present) this weekend, and have noticed some bowing on the top 1/3 of the screen

It's almost imperceptible on 16:9 content, but 2.35:1, the top of the image sags in the middle. I hooked up my PC to the TV so i could bring up static horizontal content, and it seems to be just the top middle, and the rest of the image is aligned very well.
Does anyone have any info/links about the success or effect of maybe loosening some screws or modifying the surface it sits on? My entertainment center is DIY and has a 3/4" MDF top piece that is the exact width of the base of the TV, but it sags a bit just under it's own weight. Pushing up from underneath I can't seem to affect much change, but perhaps using a stiffer piece of pine, it might keep the casing from flexing. I'm guessing most of you have very nice stands, and your Samsung smile is not caused by this...but I'm hoping this is my cause

I have enjoyed this TV very much so far, and it's immersing enough that I'm not bothered by the obvious sag in 2.35:1, but at a glance or viewing casually I find it much more noticeable. I did get it at a brick and mortar, so I suppose an exchange could be tried. Will CC let you take the new one out and see if it's better, or do they just swap and take the old one regardless?