A BB30 bearing requires loctite 609. Simple as that. Not grease, not thread locker, loctite 609. Not using the stuff can lead to creaks. Using the stuff eliminates the creaks.
People seem to be be very reluctant to use the proper stuff and use grease instead. BB30 or other pressfits don't have threads and hence require no grease or threadlocker. They require their own compound.

Also the press cups for BB30 are not that expensive and work well with the washer threaded rod system.