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We have a customer with a Valcom 1030 PA system and we’d like to integrate the Snom PA1 into it. Presently, the existing on-premise PBX appears to be powering the speakers on a relay – when the paging call is made, the speakers are powered and the announcement is heard. We can use the PA1 to provide the SIP connectivity and announcement via the speaker output, but is it possible to power the PA horns using the PA1 also? If so, how can this be achieved? Presumably using he 4 pins on the unit, but I'm struggling to establish exactly how?