The sound bar is designed to turn on and off with the TV.
Some Smart TV’s don’t fully turn off when you hit the power button. The computer inside is in stand by so it can wake up and run updates in the back ground, even when the screen off.
Some of these Smart TV’s turn on the optical port when it wakes up to run these updates. Our bar detect the optical port coming on and wakes up. If this happens to you, contact your TV manufacture and file a bug report so they can fix this glitch in a future update.