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Every time you turn your strip off or unplug the tv you are in effect starting the set from day one. Thereby forcing you to auto scan all of your channel selections. Leave it plugged in and auto scan your tuning for channels that are available in your area and if it works normally it should come back on the last channel you turned it off from. If you find that in the morning it continues to go to this 118.105 channel even after you left it plugged in then you are having a circuitry malfunction probably in the main or could be the power supply not staying live for you. Thank you for allowing me to answer your question. Please click the ACCEPT button as this is how we are paid as experts our commission from your good faith deposit and consider leaving positive feedback. Do not hesitate to ask if you are in need of further assistance and please let me know if this resolves your problem.
Thank you for these crucial and beneficial additions to your questions. Yes power fluctuations could have caused this concern. The inability to control front panel buttons is not normal unless you have turned the keypad off, which i am not sure you model even does. You may be concerning yourself with the power supply not providing proper voltages and/or malfunctioning main board. This would explain your loss of channels for a while.
Observe your power supply for stressed capacitors with bulged tops, this is a visual indication of a stress in the supply. Replace these capacitors always observing correct farad rating and temperature rating, but if able increase the voltage rating. I don't expect them to come back until the problem is repaired.
Glad to hear unplugging it again finally worked to reset.