I use a MacBook Pro, 99 % of the time with a bluetooth Apple Magic Mouse, so I don't want to turn bluetooth off. I have an Onkyo sound system at home, which everything goes through, and also accepts bluetooth connections, I don't want to turn that off. I have my MBP paired with that system so that, when I want, I can send my music to my home speakers. I don't want to unpair those.
Whenever my laptop wakes up close enough to connect to that, it connects, and my sound system switches to it, away from whatever it was, TV, game console, Netflix... doesn't matter. Laptop connects, sound system switches.
How can I prevent the MBP from automatically connecting to the sound system?