Please be advised that the Roku Voice Remote Pro would only work for all Roku TV models, Roku audio products, and most Roku players. For more information, you can visit this Support article: Getting to know your Roku® Voice Remote Pro
If you have it hooked upto roku tv with hdmi-arc, and refresh the hdmi-cec devices in the roku tv settings, then the roku tv remote will control your tcl soundbar volume via cec. This works for any soundbar brand and roku tv's. But as @RokuKariza-D says there needs to be a roku in the mix. It won't work with regular tv and non-roku soundbar alone.
Edmund Roku Community Streaming Expert
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