Several HD channels have never worked.
690, 752. There are others.
I've contacted VZ but all they do is reset the box and say it's fixed.
As a test I connected my STB directly to the ONT with about 6 feet of coax. Still same problem.
The ONT is VERY OLD. It came with the house I bought. Could it be the ONT?
Do you get any messages on STB for channel?
Do you have more than 1 STB? If so, do they all have the same issue.