Welcome to the forum, and thanks for your support of Samsung products.
Just Scan mode is not the best mode for all inputs. For some it will work, and for others, it could actually take away from the picture.
Our sets don't default to stretch mode, and I checked with our television specialist and he also noted that it's not something that is programmable within the television itself. I believe that some harmony remotes will allow you to program macros so that one button will perform up to 5 or 8 functions, so you might be able to train that macro in. Users have reported mixed results with mixed models, so I don't have a difinitive answer on the solution.
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--HDTech
Well I am a proud owner of a Samsung 40 inch 1080p series 5 that I bought on black friday. Waited two years for this bad boy and Im really happy. I just a have a few questions, I read in other posts about the white flickering bar in the just scan mode on some hd channels, and the way to get rid of that is to keep it on 16:9 which is cool. Now here is my question, I have a sony dlp in my living room and usually when I watch an HD channel it will automatically change the screen size to its best viewing quality, and when I go back to a regular channel, it will put it in wide mode which I like because I dont like the bars on the side and top. Is there a way that samsung tv can do that as well instead of having to switch screen sizes every time I change from a regular channel to an HD channel. Its pretty annoying carrying around two remotes. Also another question is about my comcast remote to my Samsung tv. I programmed the remote to my tv but the volume button only works one notch at a time, is there a fix for this? I also ordered the Logitech Harmony 520 remote just to try out, I might sell it on ebay if im not happy with it, but can I program that remote for the samsung to switch screen sizes if I needed to?
Thanks for your help.

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