I have no experience to solve your problem, although I believe that you can restore your TV to "working order". You would need to go to the Samsung Support web site that would be connected to your TV if you had registered it with Samsung. At that site there should be the "Original" firmware available or a prior version to the version that is causing the problem with your set. I would also suggest that you "try" to re-run the firmware update that seems to have caused the problem as I would guess that it was corrupted somehow before it was installed in you set, although if your set identifies the firmware as the "current version" it may not allow you to re-run it although I think it is worth a try. In any case, I am confident that an install of the original firmware or BIOS will correct the problem if it is in fact the firmware that is the issue. I have seen items go bad during the flashing of firmware or BIOS, I guess the "added stress" that the unit goes through during that process can sometimes prompt a component to fail as it was about to do and the "flash" was a "nail in the coffin" so to speak. Well I am going to look to see if I can find the earlier firmware that you will need if the "re-flash" won't correct the problem. There are forums out there that offer all kinds of software for these TV's and I go to one at times, it may have what you need so I will be back to let you know.
I have (actually had) a 40" Samsung LCD TV I was pretty happy with. As a "good" consumer I registered the TV with Samsung to receive periodic updates etc... At one point I decide to act on a firmware update available on their website, follow the instructions down to each step and install the update. The update installs successfully, except that the TV stops working properly, the image is all blurry and the colors scrambled.
I call Samsung, and the reps suggest I arrange a service call at cost. I am miffed: I had a working TV before, and only acted on an update Samsung suggested to do. Why should I pay to repair an issue Samsung itself appears to have caused? I asked to escalate the request in case the person didn't have the authority. I was told a supervisor will call shortly. The call hasn't come yet.
The TV model is LNT4061FX/XAA, and the firmware update is "LNT_61__65__66_Series_Firmware".