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# USB Accessory Audio Source Dictionary Keys

Keys for the dictionaries in the [`kAudioSessionProperty_InputSources`](/documentation/AudioToolbox/kAudioSessionProperty_InputSources) array.

## Topics

### Constants

[`let kAudioSession_InputSourceKey_ID: CFString!`](/documentation/AudioToolbox/kAudioSession_InputSourceKey_ID)

An audio input source.

[`let kAudioSession_InputSourceKey_Description: CFString!`](/documentation/AudioToolbox/kAudioSession_InputSourceKey_Description)

Audio input source description.


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