Support → SoundSource

Information for: Airfoil for MacAudio HijackLoopbackSoundSource

Working with audio from special and hidden sources

The Background Sounds special source handles background audio played via the Audio section of the Accessibility options of the System Settings app.

Captured Source

• com.apple.accessibility.heard

Finder

The Finder special source handles any audio played by the Finder, as well as audio produced using the Mac's “Quick Look” functionality.

Captured Sources

• com.apple.finder

• com.apple.quicklook.QuickLookUIService

Siri

The Siri special source handles all the audio from Siri, including both its sound effects and its spoken word audio.

Captured Sources on MacOS 14 and Higher

• com.apple.CoreSpeech

• com.apple.sirittsd

Captured Sources on MacOS 13

• com.apple.Siri

Captured Sources on MacOS 12 and lower

• com.apple.CoreSpeech

• com.apple.speech.speechsynthesisd

The Spoken Content special source captures audio produced by the system when using text reading (triggered by the Start Speaking command in the Speech menu), as well as audio generated by the Spoken Content options in the system’s Accessibility settings.

Note that while some applications send text-to-speech audio to the system process, others produce it from their own processes. Unfortunately, this means you may need to experiment to determine the exact source of text-to-speech audio. If the Spoken Content special source does not indicate activity, have a look at the application in which the text is being read itself.

This special source was introduced on MacOS 15, where it replaced the previous Text to Speech special source.

Captured Sources on MacOS 15

• com.apple.accessibility.AXVisualSupportAgent

• com.apple.Accessibility-Settings.extension

• com.apple.speech

• com.apple.UniversalAccessControl

The System AirPlay Receiver special source handles audio played directly to MacOS via AirPlay, using the system's AirPlay receiving capabilities.

Captured Source

• com.apple.controlcenter

VoiceOver

The VoiceOver special source handles all the audio from the VoiceOver experience, including both spoken words and sound effects.

Captured Sources on MacOS 14 and Higher

• com.apple.VoiceOver

• com.apple.VoiceOverQuickstart

Captured Sources on MacOS 13

• com.apple.speech.speechsynthesisd

• com.apple.VoiceOver

• com.apple.VoiceOverQuickstart

Captured Sources on MacOS 12 and lower

• com.apple.speech.speechsynthesisd

• com.apple.VoiceOver

On older versions of MacOS (MacOS 12 and lower), SoundSource offered a System Speech special source. This handles all audio spoken by the system, including Siri and VoiceOver. Due to the way the system provides this audio, it is merged into one special source. Do note that any adjustment you make to this special source will affect audio from all of these sources.

As a result of change’s made by Apple, it was removed on MacOS 13 and up, with the Siri and VoiceOver special sources serving as replacements.

Captured Sources

• com.apple.CoreSpeech

• com.apple.speech.speechsynthesisd

• com.apple.VoiceOver

The Text to Speech special source handles audio played by the system's text reading (triggered by the Start Speaking command in the Speech menu). On MacOS 14, some applications produce audio from their own processes, while others send it to the system process. Unfortunately, this means you may need to pay attention to active applications in SoundSource to determine exactly which application is producing audio. If the Text to Speech special source is not producing audio, pay attention to the application in which the text is being read itself.

Captured Source

• com.apple.accessibility.AXVisualSupportAgent