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# preferredIOBufferDuration

The preferred I/O buffer duration, in seconds.

```
var preferredIOBufferDuration: TimeInterval { get }
```

## Discussion

The value of this property indicates the buffer duration selected using the [`setPreferredIOBufferDuration(_:)`](/documentation/AVFAudio/AVAudioSession/setPreferredIOBufferDuration(_:)) method.

To determine the actual buffer duration, query the [`ioBufferDuration`](/documentation/AVFAudio/AVAudioSession/ioBufferDuration) property.

---

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