This is why cable companies push those boxes. If a channel fails then they can swap boxes. Since this is not their device, you have to decide if it's worth changing splitters, cables to see if that's it. In other words does it pick up without the splitter in line?
Two digital TV's both receive all the same broadcasts except the Panasonic will not get a single channel numbered 23.1 WVPX. It does not find it on auto scan and there is no signal if you go to 23.1 manually. Why? older tuner?
I have a Panasonic TC32LX60 (circa 2006) and a new Insignia NS-19E310A13 both receive basic cable from Time Warner Cable in NE Ohio. Neither have a cable box. Both are receiving from a split cable signal.
Time Warner is apparently rebroadcasting what would normally be air broadcasts. I do not get a satisfactory answer when I ask Time Warner.