I have hub play on a Spinergy Xaero rear wheel. I have never taken this hub apart and from the diagram on the Spinergy website
http://www.spinergy.com/bicycle/xaero_v4_specs.html it is not clear to me how the bearings or whatever is loose can be tightened. The end caps don't tighten on the bearings. New bearings? These wheels have about 6000 mi on them and they have been rebilt by Spinergy early on to correct for the hub problem the hubs had in 2000 or so.
edit: I just read on the Park Tool site: "Hubs using the cartridge type bearings are not serviceable in the sense they can be dismantled and adjusted. As cartridge bearings wear and develop play, the entire cartridge unit is replaced. Cartridge hub service is not covered in this article", so I guess it needs new bearings?