It is possible that what you're hearing is a problem in the overtones from voices and instruments hitting notes in that range. That makes sense, and so it could still be something in the compression driver. I think probably if you brought it up, you already noticed something funny about the tweeter. But the DE250 is a pretty good driver when working properly. I'd like to test it or swap it with a known good unit and see.

At any rate, I think we should re-examine this and troubleshoot the problem. Might be a damaged part, and we can easily recone drivers or replace components after we find out which one is to blame.