When I import your flow the entity gets removed from the svc node. When I try to re-enter the entity, media_player.living_room, I get an error message:
Error merging entity id into data
Also… as a side note, I did manage to get this to work. But it’s not nearly as simple as your solution. And it does have one bug. If I change the slider value then I have to change the tv volume twice before it works. Weird.
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