I tried exporting a song in midi format and importing it into Garage Band so I can record a part and ran into some problems with the drum track. I was exporting the song Blue In Green, which is a 60bpm track with brushes and very little going on in the drum track. I dragged the midi file into GB and everything parsed correctly to separate tracks. The problem is the drums notes are incompatible with GB. I used the Jazz Kit in GB and got tom hits where there should have been snare brush strokes. The other notes were wrong too. I tried transposing the notes but I couldn't make it to work.

I assume IRB exports as General Midi and GB's kits are laid out that way as well.

Any suggestions on how to get this to work?