Samsung forum: LCD TV automatically switches inputs

I have a similar problem. My unit automatically and suddenly switches sources...say from blu ray player to another HDMI source, without user involvement. After this happens, the remote cannot bring up the source list and the remote does not function except for turning the set off. The bezel controls do not work either, again, except for turning the set off. The problem is fixed by disconnecting the set fromn the wall socket for 10 seconds (until the SAMSUNG light goes off) and then turning it back on. Then the remote and bezel controls work again. This is an intermittent problem. It may not happen for a few weeks and then it might happen three times in one day. Sometimes when it happens the remote blinker on the bezel will flicker like about 10 times per second constantly until the TV is turned off. This has been happening since I took it out of the box. It's annoying if infrequent and I need to have a tech look at it. But Samsung claims that if I brinng a tech out and he cannot find the problem, I get charged for the visit.

Today i have my TV serviced by a Samsung technitian and the reply i obtained for this problem is that the main board must be replaced to solve the issue. Hopefully it will solve the problem once and for all.

It is very disapointing knowing that the quality control of Samsung is so poor. This is not a minor issue, once the motherboard must be replaced. It is a pitty the problem only started 10 days after i have received the TV, otherwise i could have demanded to change the whole equipment to a new one.

I had a similar problem with a different Samsumg LCD set. A few weeks after its warranty expired (of course), my Samsung LN46C630 LCD HDTV started randomly switching from one input to another, as if it were looking for a signal. I read a lot of blog posts from folks with a similar problem, and started down a long path of ordering and installing new boards for the TV. I tried replacing the MAIN BOARD BN94-02701J, the LJ94-03334J Controller, and the power board. None of this fixed the problem.

When replacing these large circuit boards fixed the problem, I was ready to toss the set into the trash. But in a last ditch effort, I replaced one more board: the Bn96-13451C
Assembly Board (my board was numbered BN41-01382A). AND IT SOLVED MY PROBLEM!! And here's the kicker: at about $32, it's the cheapest of all of the boards that I replaced. And I found it on amazon.com.

This p-touch board is a tiny board that takes the signal from the remote control, and from the touch control buttons on the front of the set. It's a little difficult to get at, as it is tucked behind the front bezel, and you have to disassemble much of the case to access the board. Oh, and to make things more difficult, it's connected to the front bezel with adhesive, so it's a real pain to remove without damaging the circuit components. But with some careful prying, you can do it.

Hope this helps!