SamplerPlugin example doesn't output audio

I created a project from the SamplerPlugin example, enabled “Is a synth” and “Has MIDI inputs”, built it as VST3, and in both Ableton Live and in AudioHostPlugin and my own custom VST3 host it doesn’t make any output. Playing a note clearly shows it playing back, as the playhead moves as expected in the waveform display, but it does not actually emit any sound at all (double checked in Live - no level at all in the volume meter.)

Any ideas what’s up? (Aside, seemed surprising that the default build of the project emits a plugin with no MIDI inputs! Bug?)

Thanks all!


The SamplerPlugin example is actually an MPE synth example, and it expects the incoming MIDI messages to be MPE messages. (The options for “legacy” MIDI don’t actually work in the plugin.) The reason why it doesn’t play audio is that it expects there will be messages that turn up the note volume. There might be some hack you can do in the code that adds the needed volume level message. (I think I’ve done that at some point, but I’d need to find the code…)

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You can replace the following line in MPESamplerVoice::noteStarted :

level    .setTargetValue (currentlyPlayingNote.pressure.asUnsignedFloat());

with :


To force the note volume to be up for each note.

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Thanks. Having a very hard time finding an ultra minimal sampler, so will give this a go!

Yup, that worked as a workaround. Is it worth me reporting the issue somewhere else? Thanks