Chapter One of the Defense Contract Audit Manual (located at  https://www.dcaa.mil/Content/Documents/cam/Chapter_01_-_Introduction_To_Contract_Audit.pdf )

has several sections that describe the interactions (from an audit perspective) that DCAA has with various entities within the DOD, to include Procuring Offices and Contract Admin offices)

There are other areas within the CAM that describe specific situations under specific DCAA audit activities, but, Chapter One provides the general guidance applicable to most if not all situations.