Block someone from using your home sonos

How can I block someone who is in my house in another room changing the music? Is there another way to do this without changing the passwords on spotify or pandora or my router? Changing the password to the sonos account does nothing. I wish there was a password i could set that was needed every time someone starts sonos from a different device. If you have the sonos app you only have to connect to the existing system and then Im back to square one. I wish I could see a list of active devices on my Sonos system. Then I could block those I don't want playing annoying DJ while a party is going on.