Hello David!
I need a few more details in order to reproduce what's going on.
Are you using the Special Edition organ or the DVD product Konzerthaus organ?
Which exact preset(s) or matrix(es) did you load?
If you have loaded two instruments, did you assign both of them to the same MIDI channel?
Which sound set did you load?
Which program did you choose on the Sibelius Manual Sound Sets tab?
Best regards,
Andi
Vienna Symphonic Library