Out of curiosity, I bought a bluetooth Roku ONN bluetooth soundbar today, and I love it! Everything works great with my Apple TV. But then I added my Bose headphones to Apple TV, and now whenever I turn my headphones on, I get a message saying "Share Audio: 'Onn 16 soundbar' need to be updated to be used with shared audio." How do you update a SOUNDBAR? I've never heard of such a thing before! I hope it's an easy process because I've been trying all day with no luck.
So the Apple tv is bluetooth transmitter unlike any roku which are receivers only. You paired to the soundbar by bluetooth and that works great. Alright now you want to pair the apple tv to a headphones, sounds like its the apple tv is the problem it can't be paired to two receivers at the same time.
So connect the Apple tv to a real tv's hdmi input, not the ARC if you have one. Then connect the Onn Roku soundbar to Arc input on the tv. That way the sound from the apple tv goes through the tv to the soundbar. That leaves the bluetooth open for the headphones.
I guess I should have stated my set up a bit better. I apologize for that.
I'm watching everything through the Apple TV box, so all of my audio goes from it to the ONN speaker. The newer Apple TVs have many spaces for Bluetooth equipment, and yes, only one can be used at a time, but you don't have to manually switch between them. If I'm using the soundbar and want to switch to headphones, I just have to turn my headphones on and the soundbar shuts off by itself. However, that's when I get the error message. Then when I turn my headphones off, the soundbar reconnects automatically (but with no error message).
I just want to know how to update my sound bar. I had to update the firmware on my headphones to make them work with my new Apple TV box, and that was simple. I went to the headphone maker's website, plugged them into my computer, and downloaded the newer version. I don't know where to go or how to download new firmware onto bluetooth speakers that don't have space for any cords except Optical Cable.