@crlucarelli I just saw your post and wondering if you got it resolved.
I have had no sound on NBC Channel 5 for about a week now. Oddly, It comes on for a few commercials, then goes off again and stays off during the show. Then returns immediately at commercial break. This happens for all shows...any time of day.
Channel 7 also randomly turns on visually impaired voice assistance , which is not even available on my (slightly) Smart TV. At first I thought the TV was hacked, but seeing other posts here make me think it's a Comcast issue?
You need to check the audio options for your cable box. The audio channel should typically be set to "channel default" or similar. Trying to force "English" or other may cause problems. Also, make certain something like "Audio description" is turned off.