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# AVAudioUnitComponentManager.RegistrationsChangedMessage

Type-safe notification message for audio unit component registration changes.

```
struct RegistrationsChangedMessage
```

## Overview

This notification is posted when the system’s audio component registrations have changed,
such as when audio units are installed or removed.
The notification object is the shared `AVAudioUnitComponentManager` instance.

## Relationships

### Conforms To

[`AsyncMessage`](/documentation/Foundation/NotificationCenter/AsyncMessage)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Sendable`](/documentation/Swift/Sendable)

---

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