I'll be racking shortly and will see if any diacetyl is in there...if so, I may krausen it with some spies from a current batch that I just brewed today. I usually don't get diacetyl, but I did with the Budejovice Czech yeast I used for a Czech pale and then repitched in a Schwarz Bier. It was drinkable, but to the diacetyl sensitive folks, it was just a bit too noticeable.