Guides

Virtual audio drivers and Audio MIDI Setup on a Mac

Updated 2026-09-03.

A virtual audio driver such as BlackHole (free) or Loopback ($99) is a software device that loops its own output back to its input, so one app's sound becomes another app's source. Audio MIDI Setup is the built-in macOS utility where you see those devices, set sample rate and bit depth, and build aggregate and multi-output devices around them. You need this machinery to route or mix audio between apps. Since macOS 13 you do not need any of it to record what the Mac plays.

Guides in this topic

1. What is Audio MIDI Setup on a Mac?Audio MIDI Setup is Apple's built-in utility in Applications > Utilities. It sets sample rate and bit depth per device and builds aggregate devices.
2. How to create an aggregate device on a MacOpen Audio MIDI Setup, click Add, choose Create Aggregate Device, tick each device, set one Clock Source and matching sample rates, enable Drift Correction
3. How to create a Multi-Output Device on a Mac (and keep hearing your audio)A Multi-Output Device plays sound through your speakers and BlackHole at once: Audio MIDI Setup, Add, Create Multi-Output Device, speakers first as primary
4. Is BlackHole safe for a Mac?Yes. BlackHole is an open-source (GPL-3.0) loopback driver by Existential Audio with no kernel extension; it only adds a device to Audio MIDI Setup.
5. Is Soundflower safe, and does it still work on a Mac?No on Apple silicon: Soundflower's GitHub page says DEPRECATED, Silicon Macs are not supported. Last release 2.0b2. Use BlackHole or a driverless recorder.
6. How to uninstall BlackHole or Soundflower on a MacBlackHole: delete BlackHole2ch.driver from /Library/Audio/Plug-Ins/HAL, run sudo killall -9 coreaudiod, forget the receipt. Soundflower: remove the kext.
7. BlackHole not showing up in Audio MIDI Setup: how to fix itBlackHole appears only after Core Audio reloads: restart the Mac or run sudo killall -9 coreaudiod, check /Library/Audio/Plug-Ins/HAL, then reinstall.
8. What is a virtual audio driver, and when do you need one on a Mac?A virtual audio driver is a software device wired output-to-input so one app's sound becomes another's source. Needed for routing or mixing, not recording.
9. Loopback vs BlackHole vs no driver for recording Mac audioBlackHole is free but silences your speakers until you build a Multi-Output Device. Loopback is $99 and mixes. A ScreenCaptureKit recorder needs no driver.

What are Audio MIDI Setup, aggregate devices and virtual audio drivers?

Three pieces that get confused with each other. Audio MIDI Setup is Apple's utility in Applications > Utilities. It lists every Core Audio device, sets each one's Format (for example 48 kHz, 24-bit) and lets you combine devices. It records nothing. An aggregate device is a grouping made there: several inputs presented as one device, with a Clock Source and Drift Correction to keep their clocks aligned. Apple's example merges an 8-channel and a 2-channel interface into one 10-channel device. A Multi-Output Device is the mirror image: one playback stream sent to several outputs at once. A virtual audio driver is a third-party plug-in in /Library/Audio/Plug-Ins/HAL with no hardware behind it; whatever an app sends to its output appears on its input. BlackHole is the free, open-source one under GPL-3.0; Loopback is Rogue Amoeba's $99 one with a mixer and monitor built in; Soundflower is the retired kernel extension that no longer runs on Apple silicon, as the Soundflower page documents. Put together, a typical old-style recording chain was: BlackHole as output, a Multi-Output Device so the speakers still work, an aggregate device to add the mic, and a recorder reading the aggregate. Each link has its own failure mode, which the pages in this section cover one at a time.

When do you need a virtual audio driver, and when is it just in the way?

A driver is the right tool when audio has to move between running apps in real time. Sending a DAW's master into OBS for a stream, sampling a browser into Ableton, feeding a soundboard into a call as a virtual microphone, or summing a mic and several apps into one input for Zoom: all of these need a loopback device, and BlackHole is safe and free for the routing cases, while Loopback earns its $99 when you need mixing and per-source volume. A driver is in the way when the goal is a file of what the Mac plays. Since macOS 13 Ventura, Apple's ScreenCaptureKit captures system audio for any app holding the Screen & System Audio Recording permission, and audio recorders built on it leave Audio MIDI Setup, your output device and your volume keys untouched. Most "record internal audio with BlackHole" tutorials describe a workaround for a limitation that no longer exists. The cost of using a driver anyway is concrete: selecting it as the output silences your speakers until you build a Multi-Output Device, that device disables the volume keys, its members need matching sample rates and Drift Correction, and meeting apps tend to remember the driver as your microphone. The definition page lists three cases where you need one and three where you do not.

How do you fix a driver that is not working, or get rid of one?

Two problems, two pages. When BlackHole is not showing up, the order is: restart Core Audio with sudo killall -9 coreaudiod or reboot, because the plug-in only loads when coreaudiod starts; then check ls /Library/Audio/Plug-Ins/HAL for a BlackHole2ch.driver folder; if it is missing, forget the stale receipt with pkgutil --forget audio.existential.BlackHole2ch, move the installer to the Desktop as the README suggests, right-click, Open, and install again. If the device is listed but records silence, grant the recorder Microphone permission and check the sliders in Audio MIDI Setup. When you want it gone, uninstalling BlackHole or Soundflower gives the maintainer's commands: delete the .driver folder, restart coreaudiod, forget the receipt; for Soundflower, remove the kext from /Library/Extensions and restart the Mac. In both cases remember the clean-up nobody mentions: remove the aggregate and Multi-Output Devices that referenced the driver in Audio MIDI Setup, and reselect your speakers and microphone in System Settings > Sound and in any call app. Audio MIDI Setup itself cannot be uninstalled or reset; it is part of macOS, and the devices you built are the only state it keeps.

Which Mac audio tool for which job (prices from vendor pages on 3 Sept 2026)

AirCheck, Loopback and Audio Hijack require macOS 14 or newer; BlackHole runs on macOS 10.10 and newer.

Other topics

• Screen recording with audio
• Recording internal and system audio
• Recording calls and meetings
• Recording streams, music and video sound
• Recording with QuickTime, OBS, Audacity and GarageBand
• Recording DJ sets, vinyl and instruments
• Recording lectures, podcasts and interviews
• Audio formats, quality and file size
• Fixing Mac audio recording problems
• Choosing a Mac audio recorder