I was starting to think those commands only work on actual Roku TVs even though the note mentions CEC, but my 3821 stick will control the TV's volume via voice command. It may be interesting to note that the TV is a TCL Roku TV - the remote is paired to the stick and set up to control the TV via CEC. I don't have any non-Roku TVs with CEC. I wouldn't think it should make a difference, but maybe I'll try my 4800 with the TV.
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