Are you sure it is the BH that is whistling? It could be the fletching; I assume you have shot these arrows with field points without a whistle. Try taking the BH completely apart and re-assemble it, the blades may not have seated just right, and as Midwest said; makesure they are locked down tight.

I have shot the Slick Trick 100's without any problems, don't give up on a fine head like ST.