  A superconducting Double Spoke Resonator (DSR) is the technology of choice in
a low energy section of a high power proton linear accelerator. At the FREIA
laboratory in Uppsala University, we have tested two DSRs in a prototype
cryomodule for the European Spallation Source (ESS) project. It showed that the
conditioning process of these cavity packages would be the key for the series
production tests. In this paper, we present the conditioning procedure that we
developed, and also describe the results with a special focus on the
cross-contamination observed between two high-power couplers. This study
defines a standard conditioning recipe for the series DSR production for ESS
and also for future similar projects in the world.
