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Aram Antó Comaleft a comment
One more example, may be a corner case but I use it, I have a PS4 I want to use with my computer screen, since HDMI audio output doesn't work in this case (my screen only accepts video input through HDMI) I can use a bluetooth dongle connected to my PS4 that sends the audio to this Julius app and I can play through my mac speakers, great!
JuliusTurn your Mac into a Bluetooth speaker