Set up Audio sharing to listen to music together and other use cases.

Instructions for: Windows | Mac | Linux


On Windows, sharing system audio is quite simple. Click on the caret above the mic icon within a call and select to share system audio.


Sharing audio is possible but first, you'll have to go through several steps to setup it up. Make yourself comfortable and read on!

  1. Install the Blackhole by downloading and running the installer.


    <aside> 💡 Blackhole is open-source software developed by existential audio. We are grateful for their contribution to the Mac community. If you have alternate system audio capture software such as SoundFlower installed, Tandem supports that as well.


    Once you've installed the extension, you'll need to create a new audio device that outputs both to the extension & your existing audio. Otherwise, you won't be able to hear anything while audio is sent to Tandem.

  2. Launch the Audio Midi Setup app (comes built-in with MacOS).

  3. Click the [+] plus icon on the bottom left.

  4. Select “Create Aggregate Device”

  5. Check the BlackHole 2ch box

  6. Also, check the device you want to use as your speaker. (e.g. headphones, AirPods, speaker):

  7. To use the newly created device go the the Speaker icon on the menu bar and choose Multi-Output Device (or Sharing Audio if you did step 5)

    <aside> ℹ️ Before selecting the device, make sure the volume is adjusted the way you like it. Once you have picked the output device, you won't be able to easily change volume. You can change output devices by going to System Preferences > Sound , or the menu bar if you have that option.


  1. To start sharing with Tandem, join a call. Then, click on the caret ˅ by the microphone icon at the bottom of the call window.

  1. Select BlackHole 2ch to start sharing audio with your call.

This UI allows you to send an additional audio stream to your call, in addition to your microphone. You'll want to select the device that you used to create the Multi-Output Device above, which in this case is BlackHole (2ch).