I'm left to guess that the encoding of the video isn't compatible with this TV.
I know consumers are going to write it works on some other TV and declare this means it should work. Nothing could be farther from reality.
I have Samsung TV EU32F5500AWXZH (firmware 1109) and I see that my video files are played in poor quality (quality like CamRip - all is blurry). I have checked it from USB and via DLNA - quality is bad.
The same video files I have played in another TV - LG42, quality is very high, even in small details.
Also I have connected to Samsung my old mediaplayer via HDMI - quiality become high!!!
Do you know what is the reason of this samsung problem? What can I do else, to find the reason?