Stopped horn playback
I want to be able to switch between open and stopped horn using the + and o symbols. The only way that I have found to do this is to put an invisible instrument switch next to each one. I know that stopped horn is not part of general midi, but is it possible to have the instrument set to trumpet, have the non-muted sound set to horn, and make the + and o switch from open to muted? I couldn't get it to work by right-clicking on the symbols and changing the settings there.