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"Soundflower El Capitan", tausend Infos, erster Link der hier:
https://support.shinywhitebox.com/hc/en-us/articles/206333005-Soundflower-and-El-Capitan
https://support.shinywhitebox.com/hc/en-us/articles/206333005-Soundflower-and-El-Capitan