I did the advice. Unplug the TV from the electricity and CableTV. I waited for about 15 minutes, unscrewed the back cover and looked for the keypad panel. I disconnected it from the TV base. Plug in and connect to the Cable. I tried the remote control and problem solved. I have to take the keypad card to change the buttons or get a new one. But the important thing is that the channels stopped changing on their own, or the menu appeared on the screen or turned on or off alone. Thank you for your advices.