Be careful!! You'll be blowing things up if you don't know what you're doing. Two of those leads are bringing POWER to the doorphone unit. Check out https://www.valcom.com/pdf/V-1072A.pdf

What model of Paging Controller do you have??

Valcom has a very good tech support staff, but you've got to know a bit about things first to ask questions from them. First--find your Page Controller and see if you can find a volume control on it.

You're giving me the willies

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