Apps don't have to use the TV's sound settings. So we have to explore the apps for sound settings in the apps PLUS watch out for sound options that don't work on some soundbars. Let's just say the makers haven't nailed this area yet.
Bob
I have a Samsung smart tv and a Nakamichi soundbar. When I use Netflix, Huluplus, Vudu, and Amazon prime video there is no sound from the sound bar. However using Pandora or YouTube I do have sound from the soundbar.

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