VST3 MultiOutSynthPlugin Bus activation failed


Looks like there is an issue in VST3 implementation because using VST3PluginTestHost and the MultiOutSynthPlugin example, I get a Bus activation failed

Could you guys have a look at it ?

Thanks !

When reporting issues, it’s helpful for us if you can provide details such as how the problem manifests (a crash, a jassert, unexpected behaviour), and some steps to reproduce the error. This allows us to make sure that we’re investigating the same issue that you encountered.

In this case, I see a jassert in AudioProcessor::Bus::isLayoutSupported when removing the MultiOutSynthPlugin from the VST3PluginTestHost. This is because the plugin’s isBusesLayoutSupported requires all of the output buses to be stereo, but the host needs to be able to enable/disable each bus individually. Allowing the output buses to be AudioChannelSet::disabled() seems to fix the issue. We’ll push that change shortly.

I was talking about an error message in VST3PluginTestHost own tests
If you just run those test on MultiOutSynthPlugin, you get a “Bus activation failed” error from VST3PluginTestHost.

I don’t have warning any more using the latest commit.

Thanks !

For completeness, the patch that fixes this behaviour is here: