I'm not sure which solution —there are several— didn't work for you, but if I recall correctly, I just kept trying different suggestions from this thread until something worked, and I think this was it, except I do believe the option to "turn the Audio off" was also part of my solution. Start with the star key and try these suggestions. Otherwise, go back to the beginning of the thread and try different options until one works. It appears there are a variety of solutions.
During playback of content, if you hit the * key on your remote, do you have 'Audio leveling' enabled on your device? If so, and you disable this setting"
This fixed my audio snyc problem w/ Spectrum TV channel. NOTE: did not have to change the Audio Off for the MENU volume under Setting menu.
OF COURSE it's a TV issue, and ROKU issue . IT'S A ROKU TV!!! Did you not even read the initial question where it said ROKU TV??? Please think before posting things that don't fix anything, and only make the rest of us even more frustrated!