Maybe I'm misunderstanding something.

Situation: In Skype I'd like to pick up form an USB-Mic and an application like QuickTimePlayer.

Skype is configured to use an Aggregate Device as its Microphone.

I can configure the Aggregate Device that it picks up the USB-Mic or the QuickTimePlayer, but never both!

Which one gets picked up depends on their order in the Aggregate Device config. Whatever is configured right after the Build-in Output gets taken.

In this case it is the Rode Podcaster Mic.

Hi, I successfully installed BlackHole and created a multiple-output device of blackhole and buit-in speaker. I found that I cannot adjust volume of this multiple-output device.

Hi, I would love to use Blackhole with more output/input channels, however I have no experience with coding. I understand that I can only create more input/outputs when I change the code, but I don't know how to do that and I don't have Xcode. Is there a way I can create more channels? I need like 40. Thanks

Hi,

I have tried a few things but couldn't get it to work.

I am looking to;

1. Combine the audio from Spotify
2. Headphones's Microphones
3. Route into Blackhole.

Is this possible?

In Ableton, if I set the input to device to BlackHole for the first time it works great. If I set the input device to something else, then set the input device to BlackHole again, BlackHole crashes with a Buffer Overflow.

Ableton handles it gracefully and defaults to no input device. If you try to connect to it again it works fine. (maybe because BlackHole restarts?) But there is a crash every second time you try to reconnect to BlackHole input device.

The same thing happens when you connect to BlackHole input in Ableton, close Ableton, then open Ableton again (and it tries to reconnect to BlackHole as input).

This is reproducible with Audacity as well. (I have to run Audacity from terminal as sudo for some reason). The trick to reproduce with Audacity is to actually record BlackHole once, close and reopen Audacity, then record again.

Are we not cleaning memory properly when we stop IO?

Thanks for making this!

System Info:
MacOS Catalina 10.15.3
Audacity 2.3.3
Midi setup:

Hey,

I'm really sorry to ask a question like this... I would like to increase the number of channel, possibly to 128 for my needs, and looks so simple in FAQ.

BlackHole.h is a file hide somewhere on my computer ? Or...

Thanks anyway !
GG

Recording audio with ffmpeg through BlackHole works quite well, thanks for this!

I encounter one problem though: The second execution of ffmpeg does not work. There is 3 CTRL-C necessary to kill ffmpeg. It then responds with: Received > 3 system signals, hard exiting. After that, the next ffmpeg command does work, the ffmpeg after that not and so on.

Killing coreaudiod before the second ffmpeg does help too.

It happens only if audio is or was playing at the first ffmpeg command.

I tested ffmpeg version 4.2.2
You may test it using this command:

# Get input channel number for BlackHole device
ffmpeg -f avfoundation -list_devices true -i ""

# Record 2 seconds from i.e. input channel 0
ffmpeg -loglevel debug -f avfoundation -i :0 -t 2 test.mp3

-loglevel debug shows much, interesting is this:

First ffmpeg call:

...
[avfoundation @ 0x7f8843000000] audio device 'BlackHole 16ch' opened
[avfoundation @ 0x7f8843000000] All info found
...

Second ffmpeg call stops at audio device 'BlackHole 16ch' opened

Recording through other input channels like Built-in Microphone does work multiple times, as expected.

Any idea what may be wrong here?

Thank you for this brilliant work on BlackHole development... looks super interesting.
I've tried BlackHole on Mojave-based MacBook Pro (2018 15inch 10.14.6). It works if it's single-channel BlackHole output->BlackHole input, but it doesn't work if I use composite output composed of BlackHole output and headphones or speakers output. Is there any method to compose an aggregate output device with BlackHole in Audio MIDI Setup app?

Hey!

If you want to become n°1 replacement for Soundflower then please add some screenshots... and maybe have a website with a binary? That would make the decision easier if I want to use/try/love it or not.

Cheers

First off, I'm excited by this project, and look forward to experimenting with it. Thanks for putting it out there.

Could @devinroth speak to motivations for this project relative to the Jack connection kit? Is there something that this project offers (or will offer) that Jack does not?

Hi Blackhole team,

Since installing blackhole (among other programs to be fair), I have had some system wide crashes where all applications shut down and my computer almost goes into total lock down where I cannot restart/shutdown manually but have to resort to sudo reboot.

I have been monitoring the issue for a while and found two crash logs which coincide time-wise with this crash event happening.

The logs are attached here:

crash1.txt
crash2.txt

It is entirely possible blackhole has nothing to do with this, but the crashes appear after the phase in which I moved from JACK to Blackhole and not before. Also, there is nothing else in my logs I can find related to the crash.

Would someone be able to have a look at this and investigate the possibility that Blackhole is doing something unintended?

The latest release v0.2.4 is not working for me. I'm using macOS Catalina. Tried installing and restarting a couple of times. ;)

The v0.2.3 release works though.

Bonjour et merci pour cette appli bien necessaire. Je voudrais utiliser Blackhole pour router 36 canaux audio. J'ai bien lu la notice qui propose de le faire mais je ne comprends pas la methode, en tout cas je ne trouve pas balckhole.h.
Pourriez vous m'éclaire svp
merci

Thanks

You mentioned Build Installation instructions on https://github.com/ExistentialAudio/BlackHole#advanced-customization

But I cannot find it...

I run this command to install BlackHole.

brew cask install blackhole

Log

==> Purging files for version 0.2.6 of Cask blackhole
Error: Failure while executing; `/usr/bin/sudo -E -- /usr/bin/env LOGNAME=jimmysong USER=jimmysong USERNAME=jimmysong /usr/sbin/installer -pkg /usr/local/Caskroom/blackhole/0.2.6/BlackHole.v0.2.6.pkg -target /` exited with 1. Here's the output:
installer: Package name is BlackHole.v0.2.6
installer: Installing at base path /
installer: The install failed. (The Installer encountered an error that caused the installation to fail. Contact the software manufacturer for assistance. An error occurred while running scripts from the package “BlackHole.v0.2.6.pkg”.)
Follow the instructions here:
  https://github.com/Homebrew/homebrew-cask#reporting-bugs
/usr/local/Homebrew/Library/Homebrew/system_command.rb:176:in `assert_success!'
/usr/local/Homebrew/Library/Homebrew/system_command.rb:53:in `run!'
/usr/local/Homebrew/Library/Homebrew/system_command.rb:29:in `run'
/usr/local/Homebrew/Library/Homebrew/system_command.rb:33:in `run!'
/usr/local/Homebrew/Library/Homebrew/cask/artifact/pkg.rb:59:in `block in run_installer'
/usr/local/Homebrew/Library/Homebrew/cask/artifact/pkg.rb:65:in `with_choices_file'
/usr/local/Homebrew/Library/Homebrew/cask/artifact/pkg.rb:52:in `run_installer'
/usr/local/Homebrew/Library/Homebrew/cask/artifact/pkg.rb:34:in `install_phase'
/usr/local/Homebrew/Library/Homebrew/cask/installer.rb:218:in `block in install_artifacts'
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/set.rb:777:in `each'
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/set.rb:777:in `each'
/usr/local/Homebrew/Library/Homebrew/cask/installer.rb:209:in `install_artifacts'
/usr/local/Homebrew/Library/Homebrew/cask/installer.rb:101:in `install'
/usr/local/Homebrew/Library/Homebrew/cask/cmd/install.rb:22:in `block in run'
/usr/local/Homebrew/Library/Homebrew/cask/cmd/install.rb:16:in `each'
/usr/local/Homebrew/Library/Homebrew/cask/cmd/install.rb:16:in `run'
/usr/local/Homebrew/Library/Homebrew/cask/cmd/abstract_command.rb:36:in `run'
/usr/local/Homebrew/Library/Homebrew/cask/cmd.rb:92:in `run_command'
/usr/local/Homebrew/Library/Homebrew/cask/cmd.rb:158:in `run'
/usr/local/Homebrew/Library/Homebrew/cask/cmd.rb:123:in `run'
/usr/local/Homebrew/Library/Homebrew/cmd/cask.rb:9:in `cask'
/usr/local/Homebrew/Library/Homebrew/brew.rb:103:in `<main>'

Set up with BlackHole.v0.2.6.pkg also failed.

I have changed the Security & Privacy.

Hi,

I build a 2 channels version of BlackHole with Xcode but it could be nice to rename the driver like "BlackHole(2ch)" to keep both the 16 channels and 2 channels.

So, what do we have to change in the code to achieve that ?

Thanks !

Best,

Jean

Hi there,
I am trying to let Shazam recognise songs as I play them (e.g., youtube compilations).

I successfully created a multi-output device with Built-in Audio (Master) and Blackhole (Drifted).
I did some tests and everything's fine (e.g., I am able to record on Logic Pro whatever I'm listening to).

However, Shazam seems to get no audio: it's not able to recognise even the most famous songs of all times.

Any thoughts? Am I missing something?

When I am configuring BlackHole's output as surround device (e.g. 5.1) in speaker configuration of macOS Audio MIDI setup, the channel order is not stored, it always goes back to 1:L , 2:R and other channels are not assigned. My OS is Sierra (10.12.6).

btw. BlackHole is awesome! Great job!

If the audio output is set to Headphones, HDHomerun (silicondust.com) works normally decoding video and audio.

If the audio output is set to BlackHole 16ch, HDHomerun starts up and decodes video, but audio is silent. I think this would be expected.

If the audio output is set to Multi-Output Device, HDHomerun is blocked and does not display the opening screens. To close the program I must use the menu Quit option as the "X" does nothing.

Hi, I'm on mac catalina, and the plug-in works perfectly for screen recording audio, but now I'm seeing an issue with it when I make or receive calls on my mac via FaceTime. I have the sound settings back to microphone and internal speakers, but I cannot hear calls and the caller can't hear me. Any thoughts?

Hi,

I just installed v0.2.5 of blackhole and tried to record audio beside I wanted to hear it. Here are some points I setup to do so:

1. Created a multi output device within the Audio-Midi-Setup with the primary device being set to the internal speakers - drift correction applied to BlackHole 16ch
2. Started the system preferences for audio and set the input to BlachHole 16ch
3. Started Audacity and set the recording device to BlackHole 16ch and the output to the multi output device

What I am facing is that in the system preferences the input is recording the signal correctly - I can see it right there, but Audacity is not recording anything.

Any Ideas what I made wrong?

Beside that I am using macOS 10.15.2, Audacity 2.3.3

Thanks a lot and kind regards

Note: QuickTime is recording the audio without any issues. Maybe it is related to Audacity but I just wanted to ensure.

it appears to have a 500 server error

Hi, I'm trying to troubleshoot using BlackHole for some basic routing. I was struggling to get anything to route at all so I tested my setup using a trial version of AudioHijack.

I am routing like so:

Audio Interface -> Logic Track -> BlackHole Input 1

I would then like to send BlackHole Output 1 to another app (Mobius Looper). In AudioHijack the routing above all works, and I see levels for the interface and the BlackHole Input 1, but BlackHole Output 1 does not show any signal.

I'm not sure how it can be that BlackHole Input is not connected to BlackHole output, so I'd appreciate any thoughts for troubleshooting this! Screenshot below

Thank you

Edit: I’m on Mojave and I also have Soundflower installed, will try removing that today to see if it affects.

Hey all, so I don't know where down the workflow this is not working but I can't seem to get this to work with OBS.

For output device in OBS, Blackhole is not listed. OBS is listed as a microphone source in Privacy and Security.

Any help would be appreciated!

I've installed it through brew. In rack I choose it as an output, and in garage band I add a new audio track and choose the first channel of black hole as an input. The output of the garage band is set as a multi output device which is made of default output and black hole. When I press record in garage band, I can not hear anything and neither does it record anything. Monitoring in garage band is turned on. What am I missing?
macOS Catalina

Downloaded and installed but can't get system audio from Safari page to show up in Quicktime Player or Uniconverter (screen recorder tool) all inside Catalina 10.15.2

Really baffling. Under Mojave I had Soundflower working fine for this same function.

Any help is appreciated.

Thanks.

I'm trying to record the audio from a Google Hangout through Adobe Audition, but none of the input channels seem to be giving me anything. But, when I record audio from, say, YouTube, it records perfectly. I'm using a mic connected to a Scarlett 2i2 audio interface and the setup that I've gotten to work correctly is:

Audio MIDI Setup
Aggregate Device named Scarlett & BlackHole:

Multi-Output Device:

Sound
Input:

Output:

Audition Audio Hardware Settings

Audition Tracks

That's a recording of both my mic and youtube playing at the same time. If instead of Youtube, I try to record the sound coming from either a Google Hangout or Facetime, the levels are completely flat and nothing records.

I've also included Built-In Output in the agg and multi-out setups as per the wiki instructions, but I still get no audio recording regardless.

The one thing that I found strange is the naming of the Scarlett Inputs in Audition.

Its labeled as BlackHole 16ch Input 1 and 2? It doesn't affect anything with the youtube recording, and I've tried using the BlackHole inputs 3-16 but no sound goes in or comes out when I use them. I'm new to all of this so I'm not positive if I'm screwing up somewhere.

Found this project when trying to use SoundFlower on Catalina. Thanks for developing!

Is it possible to use BlackHole to record audio when record screen using system recording tool (QuickTime Player) and also can listen to system audio from speaker? Currently I have to set output as BlackHole in both Sound and Screen Recording to record system audio. But I can not hear system audio under this situation.

Compared to other screen recording tools like Snagit and ScreenFlow, I found they both have slight latency in sound for recording system audio. There is no latency when using BlackHole with QuickTime. However, can not listen to audio is a problem.

BlackHole is not showing up in preferences. Do I have to disable System Integrity Protection?
I am using macOS 10.15.2.

Any idea why It's not working?

Hi, Cool that you have built this. well done!

I've been trying it out, feeding 8 channels of Traktor DJ output (4 stereo pairs) into blackhole and then picking them up Ableton to play alongside prerecorded tracks from Ableton. I'm finding the Trakor tracks via Blackhole have a greater latency doing this than using the equivalent loopback feature on my RME soundcard. I don't always have my sound card available so it would be great to have the option to use this. Any idea why this is?

I also get quite bad glitching after a while. Is this to do with the clocking issue raised in #27? ie the "blackhole" input interface is not synced to the "internal audio" output interface of my macbook in Ableton?

Best, Tom

First try out, works perfectly on Catalina GM, thanks for your work, please keep it up : )

I followed the instructions and can't seem to get this working. I noticed when setting "Use this device for Sound Output" on the Multi-Output Device, Apple Music, YouTube (in Chrome), and Quicktime player won't even play. Youtube videos even stop when switching to this output while playing. And i can't press play to resume. The scrubber on the timeline doesn't even move. Its almost as if macOS knows what we are trying to do and stops anything from working. haha. Both garage band and Logic have access to the microphone in system preferences. Not sure what else I could try.

I cannot get the audio from BlackHole into Audacity. I followed all instruction and selected BlackHole as the recording device but no audio is entered. Any suggestions?

Hi

Firstly, thanks for making this wonderful driver.

I have one question: I am unable to manipulate the volume when i route audio via blackhole. What's the trick?

The volume level slider has no effect on the output stream either via the finder menu bar or the Audio Midi Setup app.

When I used Soundflower previously the volume level slider worked which was quite convenient.

He,

I'm trying to compile again a two channels version of BlackHole by following the wiki instructions.
The compilation succeed. So I changed the name of the folder and copy it in the right folder next to the 16ch version as what did in November.

But after the "sudo killall coreaudiod" command I find just one BlackHole with a strange mix regarding the name on the left which displays 16 channels and the number of in/out on the right.

Can you help please ?

Best regards,

Jean

BlackHole doesn't seem to set the sample rate based on the actual stream as requested by an application, or at least it doesn't show it on the MIDI panel. Tested with Audacity and IINA player. Verified with IINA player -> Hecate USB SPDIF out card -> Roland Quad Capture SPDIF input, Roland MIDI panel shows the correct input sample rate.
A test program that reads an input stream from the Blackhole inputs and displays the actual audio sample rate would be greatly appreciated. Test case would be a) launch test program with nothing playing and Blackhole mnually set to 48KHz, b) play a 96KHz file and verify that the sample rate is correct, c) play a 192KHz file and verify that the sample rate changes to the correct value.

After installing BlackHole (followed instructions including restart), I set all my input/output to blackhole, and tried recording from audacity, but it's a flatline. I changed the audio settings to BlackHole in both the system settings and audacity. I am seeing that it is successfully routing through because macOS is registering an input through BlackHole, but it doesn't seem to extend to audacity.
I have tried the following:

1. Restart audacity
2. Turn Transport Options > Software Playthrough on/off.

Any thoughts? I'm assuming this should work with any DAW. I'm going to try reinstalling Audacity. Otherwise I might have to wait for Soundflower to add Catalina support.

Catalina says won't let me install because might be malware, what's the work around?

I cannot change the volume while using BlackHole. I'm not using it through multiple-out device like mentioned in #16.

Or, is it a limitation of BlackHole?

I could change volume when using soundflower.

I'd like to use AU Lab to perform some EQs on Catalina.
I'm using the same setup that worked fine with Soundflower.
Did anyone try it already?

o/

Hi, I love your piece of work. I'm using is to route audio from Ableton Live to my own application written in cycling 74 Max. It works perfect. When I quit all applications and restart them all audio is still routed from one to the other application. But when I close the lid of my macbook Live forgets BlackHole was the selected audio output device. So I tried making an aggregated audio device with just BlackHole in this device selected, but then still Live forgets this Aggregated device when I close the lid. I'm letting other people work with this setup who are not aware live's in the background. You can imagine I don't want to send them to the live preferences every time they close the lid of their Macbook. I'm on a late 2019 16" Macbook Pro which shipped with Catalina (10.15.3)

FYI I also posted this question with Ableton.

But again, what great work have you done!

In windows, we can capture audio directly from speaker, anyway to do it by BlackHole?

I have blackhole downloaded and installed on Mac OS 10.15. First off should there be an application in the apps folder? I have played around and set Audio Midi Setup yet I'm not sure things are working properly. I am trying to record auto from a video online and it still the sound still have that low echo type sound to it. I played around with Audio Hijack and when doing so the sound came out clear...I was under the impression this would be aiming to do that same sort of thing...Can anyone support me with this?

I've tried to install BlackHole: it puts up a dialogue saying it installed successfully, but I can't find it anywhere. This is on Catalina, 10.15.1

Any ideas?

Regards,
David

Hi,

I just tried to build a 2ch version with the instructions on the Wiki. Finally the two devices are visibles but they are named "BlackHole 1 " & "BlackHole 2".

So no number of channels in the name. Is it normal ?

I used Xcode 10 on High Sierra..

Jean

It also causes the audio from other programs to stop, ie youtube

also funny how I can't change anything here

Originally posted by @quantuminformation in #54 (comment)

I tried to install BlackHole few times, but I can't find the software anywhere on my computer. Is the installation failing or maybe I missed something.
Any ideas ?

Unable to remove on Catalina because it seems some files in Library can't be removed.