Years ago I built a wheel with a CK tandem hub and it was very loud when coasting.
Yes, they have a very loud and distinctive angry bee "buzz"; it's the sound of $$.
I also had problems with it skipping with hard pedaling.
Did you adjust the rear bearing pre-load after building the wheels and several times thereafter during the break-in period? If not, engagement slip is one of the first things that you'll begin to notice. Again, CK hubs have some very specific maintenance requirements:
http://chrisking.com/tech/tech_hubs
The seals were very tight which created a lot of drag.
Compared to???? To be fair, White Industries hubs seem to have the 'free-ist' spinning bearings out of the box vs. most others. Of course, their bearings also wear out in fewer miles vs. the higher quality bearings used by CK, Phil Wood and some of the other companies. Again, this is just my observation based on owning and riding examples of all these hubs over the years plus several others.