Or it's not connected or you're on Comcast which recently moved to all encrypted channels which means you can not connect this input without a cable decoder box.
Also, try a factory reset (see product manuals and find the word reset and read how to reset) rather than changing this one setting.
I recently hooked up an air antenna to test it out. Went into tv program and switched from cable to antenna.
Now I'm trying to get back to cable and no matter what I do it doesn't work. I have selected cable as my source, checked that all the cords are connected in the right places, and run auto scan numerous times. I keep coming up with zero channels.
Help?

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