In a situation where you may want to pack the surface away as soon as possible but the PA still needs to run, connect a PL10 or PL6 to the MixRack and assign some basic functions to the controls such as master PA level (can be DCA), DJ / Announcement / media feed levels & mutes etc.

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This is also a solution for venues where often the surface & house tech are not required to attend to get basic setups & sound control. Maybe assign some soft keys to some scenes for starting levels, shutdown etc.