Specify this mode if your app is performing measurement of audio input or output.
- iOS 5.0+
- Mac Catalyst 13.0+Beta
- tvOS 9.0+
- watchOS 2.0+
This mode is intended for apps that need to minimize the amount of system-supplied signal processing to input and output signals. If recording on devices with more than one built-in microphone, the primary microphone is used.