The WTSD-PWHUB is designed to be used in conjuction with AtlasIED WTSD wall plate mixers at the head-end (amp rack) in place of the WTSD-PWBOB when additional headroom control and external device integration is necessary. The WTSD-PWHUB provides an emergency audio mute for fire systems and two NO / NC relays, one that is activated automatically by the auto sleep function and one that can be manually activated by a local latching “System Priority” button on the WTSD-MIX31K or WTSD-MIX41K.