I just hooked up a Vizio SoundBar to my friend's Vizio TV via Optical. The TV is connected to a Roku Ultra via eARC. Guess what? The Roku remote controls volume level on the Vizio SoundBar! How is this done? I am assuming there is a new protocol to send control codes over TOSLInk. Let's discuss...
No, they haven't, optical imput has nothng to do what IR commands the front of the vizio soundbar accepts. It could have nothing connected to the soundbar at all, just power, and the vizio tv commands would still be accepted, its just how vizio makes the components work together. Other tv brands who use the same IR commands as vizio tv's like Goldstar, LG, RCA/Proscan, their remotes would control the vizio soundbar as well. Even Roku tv brands like Hisense and Sharp use the same vizio volume commands.
Edmund Roku Community Streaming Expert
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