I had trouble with the uni.com hub too. I tried two different hubs with nimbus cranks and BE cranks, and they always came loose quickly, even when using red loctite on the tapers.
I finally solved my problem by using “liquid weld” on the tapers. (basically epoxy).
it was fun while it lasted…its now in Florida.
Have you tried using grease on the tapers and Red Loctite on the bolt? I have 2 unis with Nimbus-X cranks on both. Installed with greased tapers, red loctite on the bolt using a torque wrench and they are still as tight as the day they were installed.
Adam sold it.
Now it’s in Richmond, VA, and going back to a 24" while I wait to put shorter cranks on the 700x35c.
the postal service has more miles on that frame than any two legs will ever know.