Yesterday evening I was watching channel 4 on my 6 months old Samsung 42” tv and decided to have a look at Ch3. The picture appeared for about 10 seconds and then disappeared. Have tried lots of times since then but the same thing happens: picture appears and then disappears. No other channel is affected, only Ch3. If I swap over to Ch103 there is no problem and I can watch the programmes there. Advice would be much appreciated.