Mono/Mono AU fails to load in Live, "This Audio Unit plug-in is not compatible. Failed to initialize."

[apple412]

Keeping up the nice conversation with myself

I found this older post that seems to indicate that it should be one or the other (JucePlugin_PreferredChannelConfigurations OR isBusesLayoutSupported) but not both?

Projucer Audio Plugin standalone

Sorry I should be more clear. In JUCE you either choose to use the JucePlugin_PreferredChannelConfigurations define or override isBusesLayoutSupported. In any case, if you are using the standalone target, then you need to alter your plug-in so that it supports zero channels as an input. This means that you would have to alter the Projucer’s audio plugin default template code to also support zero input channels, when adding the standalone target to the project. If you are using JucePlugin_Prefe…

It seems that in my experience you need both for VST and AU to properly work together.