speaker setup on apple tv

When I turn on my AppleTv (4th gen), it connects to a bluetooth speaker. I don't want that. I use HDMI output to feed my Surround system, now some twinky bluetooth speaker. When I shut down the speaker, which is in my bedroom, not near the apple tv, then my living room tv decided to feed audio to my bedroom apple tv. How can I lock things down so I don't always have to set up audio???