Kind of a similar thing here. I just put the BB back in the Centurion mixte rebuild I've got going. Everything looked very clean when I disassembled it, so I have not even changed the bearings. [shame] But there is an occasional slight kind of slushing sound from the drive side. I opened it up, made sure all the bearings were present (they were), added some grease and reseated them, added some more grease for good measure, and put everything back together. Sound is the same, possibly a bit less. I did apply grease to the spindle.

The spinning is easy and smooth with the BB adjusted for no slop. This is not exactly a high performance bike so I'm not going to go crazy over a little occasional noise but...

[edit to add: you guessed it, I went back to the basement. 'Remember honey, we have Susan's party tonight!' 'Yeah, I'll just be a minute!' Removed the L crankarm, spun off the lockring and adjustable cup, looked inside, pulled out the plastic sleeve, put the cup back on, spun it some, pulled the cup, put the sleeve back in, tightened the cup and lockring back down, crank back on...and it's fine. It sounds like ball bearings spinning in grease. That's my story, and I'm sticking to it. ]

ps: sorry for the threadjack, Pars. Good luck with yours!