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You are trying to run 32-bit VST/AU plugins (Catalina dropped 32-bit support entirely). Fix: Only use 64-bit Audio Units. Run your plugins through a validator like AU Lab or update to the 64-bit version of the plugin.

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I understand you're looking for for macOS Catalina (10.15.7) . Here’s the accurate information you need. You are trying to run 32-bit VST/AU plugins

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