Glitch with Certain Guitar Sounds

I am running into an issue with the “distortion guitar” and “overdrive guitar” sounds from the default VST. When in Dorico, I am guessing there is a problem with the MIDI as randomly the guitar will play and hold a loud C1. In Dorico, I have found that if I create a dummy instrument with the same VST slot, put in a C1 at the beginning and set CC 007 to 0, it fixes the problem. However, when I want to export audio, the note sounds on every individual instrument. Is there any way for me to remedy this?


This is due to a key switch. Some VSTs use key switches to changes sounds, such as triggering palm muting. When the key switch being triggered isn’t used by the VST, the result is a low pitch.

Read through the section in the the manual on expression maps, which covers key switches. Should help you understand how to set up the expression map and key switches correctly, which will solve the low note problem.

If you’re still running into problems, post the project and I can take a look.

Thank you for the advice. If I’m going to be honest, that side of Dorico is still a bit daunting and I couldn’t get that to work. I think that it might be a problem with Dorico since that note played back even when soloing channels that don’t have any sounds attached. I found that changing the patch from “[GM 031] Distortion Guitar” to “Distortion Guitar VX” fixed the problem, probably since [GM 031] doesn’t have any key switches attached whereas Distortion VX does.

If you change the sounds manually in Play mode, then you also need to check whether or not the expression map assigned to that channel – which is what determines how Dorico will handle things like playing techniques, slurs, articulations etc. when it determines how they should be played by a particular sound – still makes sense. Chances are that it doesn’t. So go to the Endpoint Setup dialog and try changing the expression map for your guitar instrument to e.g. Default.

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