Yes. I've had this problem on both XP and Vista machines. When importing a BIAB arrangement into RealBand, the volume differences between tracks can be quite different. Most of the time, the RealDrums are much lower in volume than the RealTracks.

You may want to try a realtime recording instead of Rendering and see if that is better. If not, try Rendering the tracks to separate Wav files and do your mixing elsewhere.

R