Try to reset the TV back to factory settings that may help by pressing the exit button for 20 sec's
I have a Samsung LE40B650 which is only 18 months old and about a week ago all the hdmi ports will no longer show any picture. If I unplug the hdmi lead it does show not connected so the port does see something. However no matter which device or cable I try I just get no signal. I have an xbox 360, blu ray dvd and a virgin hd box and none will work on any of the ports. I have tried a factory reset but this did nothing. Does anyone have any suggestions or have they experienced the same issue?