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# isEnabled

Determines whether the bus is active.

```
var isEnabled: Bool { get set }
```

## Discussion

Hosts must enable input busses before using them. This allows an audio unit to be prepared to render a large number of inputs, but avoid the work of preparing to pull inputs which are not in use.

This version 3 property is bridged to the version 2 `kAudioUnitProperty_MakeConnection` and `kAudioUnitProperty_SetRenderCallback` APIs.

---

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