Kernel extensions must be approved during the first installation of the corresponding driver. If user approval is missing for some reason, the driver will not be loaded and the corresponding audio interface will not work properly or will not be available, neither in any DAW nor in Audio MIDI Setup. This affects audio interface drivers that make use of kernel extensions. With macOS High Sierra, Apple introduced a security feature named 'User-Approved Kernel Extension Loading' which requires user approval before loading a new third-party kernel extension. One with a black icon and one with a red icon. If Audio MIDI Setup is listing the audio interface as shown on the following two screenshots, the driver installation failed and the device is not working properly.Įrror: Audio MIDI Setup showing the UR22C with a black icon.Įrror: Audio MIDI Setup showing two entries for the UR22C, In case the audio interface is not listed in Audio MIDI Setup, the driver installation failed and the interface cannot be selected in the DAW. This is what the Audio MIDI Setup looks like when the audio interface is working properly: Audio interface cannot be selected in the DAW and is missing in Audio MIDI Setup.The audio interface selected in the DAW cannot play back or record audio.After starting the DAW (Cubase, Nuendo, or another audio application), audio can no longer be played back in iTunes.On macOS 10.13 (High Sierra) or newer, one of the following issues with your audio interface occurs, even though the latest driver has been installed:

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