Note: This issue has also been reported using feedback assistant: FB23098465 We observed that with Logic Pro version 12, the Logic Pro application process crashes systematically if an audio unit takes more than 20~30 seconds to initialize. The audio unit is loaded from AUHostingServiceXPC process, which does not crash, only the Logic Pro process crashes. As a plugin developper we are trying to do our best to reduce the Audio Unit initialization duration in order to avoid this crash, but we do think that Logic should not crash in this scenario. The Feedback Assistant report contains detailed information including: the Logic Pro process crashlog A basic test plugin that triggers the crash to help you reproduce the issue detailed analysis of the issue, system profile, ... Since we did not get any answer on feeedback assistant so far, any feedback will be very much appreciated :) Thank you for your help