Dictation on Mac Air M1 not working with BlackHole for external recordings

I am trying to use dictation on a 2020 Mac Air (M1 chip). It works fine using the built-in. microphone, but I want it to transcribe recordings made on an Olympus digital recorder, and this is proving difficult to set up. I have installed a BlackHole 2ch virtual audiocable (from https://github.com/ExistentialAudio/BlackHole) and everything seems to work - for example, if I set up the sound input as blackhole and the output as speakers I hear the audio, so presumably the data is getting through the virtual cable - except that no dictating actually happens.

Any advice on how to get this setup to work?

Posted on Oct 5, 2026 12:44 AM

1 reply

WheelieNick

Level 9 (74,110 points)

Oct 10, 2026 12:51 AM in response to ThePatHayes

Hi there

Please try this

Microphone Permissions: Go to System Settings > Privacy & Security > Microphone and ensure that the app you are using for dictation or transcription has permission to access your microphone.
Open Audio MIDI Setup: Press Cmd + Space, type Audio MIDI Setup, and open the application.
Create an Aggregate Device: Click the + button in the bottom-left corner of the Audio MIDI Setup window and select Create Aggregate Device.
Configure Inputs: In the list on the right, check the box to include BlackHole 2ch (and ensure drift correction is checked if combining devices).
Set as System Input: Right-click your newly created Aggregate Device in the sidebar and select Use This Device For Sound Input (or select it directly in System Settings > Sound > Input).
Route Audio: Play your Olympus recorder or audio source so that it outputs into BlackHole 2ch, and macOS Dictation will process the stream from the aggregate input.