This issue was discovered on Discord, not sure which operating system or version, but I have reproduced it on 1.2.0-RC5 on Windows 10. When opening an existing project containing the Transient VST plugin, a stack overflow occurs in RemoteVstPlugin.exe. This seems to be because the plugin calls hostCallback(audioMasterAutomate, ...) in response to setParameter, but we call setParameter in the handler for audioMasterAutomate .