With mine I had to hold "F" down and then, while holding down the "F" button, press the mtue button. It sounds pedantic, but it took me 10 minutes to work it out. Mind, I'm not the brightest spark.

Hi i have a tv sonwa on the botton left of the screen there is a red key tv does not work can you tell me how to unlock it Thanks Rob

the F & the mute button worked treat, thank you very much. It was starting to get on my nerves. 2 days with no TV. thanx again.

its happened to us and found it by mistake .press f button and mute at the same time and it is located at the bottom of the remote steven

Ask your mom or dad or siblings. they should know. or if you still have the thing it came in, read it and it proubly says how to. Bye!!!!! ttyl