We have found that certain freehub bodies may interact with our cassette in such a way that noise can occur under load. We have made changes to newer production runs of the cassette to solve this potential problem.
Follow these steps to cure your creak, if you detailed install and removal instructions you can find those here: http://service.bythehive.com/c/Cassette
Grease under the 9-10t cogs on the steel portion of the cassette.
If greasing doesn't solve your issue, contact your nearest distributor for a creak fix kit. The kit includes a spacer and small PTFE washer.
Remove your cassette, install the silver spacer under the cassette
Re-install the aluminum cogs and lockring
Install the PTFE washer and make sure it is seated on the XD driver
Re-install the steel portion of the cassette.