In my setup, I use the -9db audio offset for the unselected decks, feed all of the spkr out's through a level converter, summing mixer and audio power amp to feed the speaker. The summing mixer was modified to have mechanical stops to ensure that audio is never fully muted in the mixer, and was installed in the console in such a way to allow adjustments if necessary, but is protected enough to ensure that those adjustments are not made accidentally.
View attachment 84004