Random, non-notated notes being played

I’ve got a ghost in my chart :astonished:
Can anyone help me locate it?
It’s the first beat of the Electric Guitar part and it’s an invisible low low C.
2020-06-12 21-39-45_Bridge Over Troubled Water (reggae).dorico.zip (802 KB)

You have the wrong expression map for the Electric Guitar.

You are using the HSSE nylon guitar map, which uses note C0 as a key switch for “unmuted” (i.e. normal) sounds. That’s where the low low C is coming from.

Try the “default” expression map instead. There doesn’t seem to be any other obvious choice available.

To change it, go to VST instruments panel on the right hand side in Play mode, and click on the cog-wheel icon.

That fixed it, thanks! I would never have thought to look there. Dorico pulled a quickie on me by popping HSSE nylon guitar map in there. I never selected it (consciously). I might have chose that sound in passing, but as soon as I chose a different sound, it should have changed, right?

This is not how Dorico works. When you change something by hand in the VSTi (here from nylon guitar to electric guitar), Dorico no longer deals with the VSTi settings, assuming you know what you’re doing and not messing with your choices. The only way to give Dorico back the power is to do Play menu> Playback Template > Choose (again) a playback template and apply.
In your case, it would have been automatic if you had never changed anything to HALion but instead had performed a “change instrument” in the guitarist player’s card menu, in Setup mode. Choosing electric guitar should have changed the playback instrument as well ass its settings (playback expression map)
Hope it helps!

Ah okay. Well now I know I need to actually know what I’m doing when I get into the Halion weeds! Thanks!

Unfortunately there is no way (at present) for Dorico to find out that you’ve changed a sound in the VST instrument; while it might be possible in the future for us to make this work automatically for HALion, it’s not in general possible for VST instruments (I believe something might be possible with VST3 instruments, but it’s completely impossible with VST2.x instruments). So if you make any manual changes in a VSTi, you need to inform Dorico of the change via the Endpoint Setup dialog.