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  "identifier" : "/documentation/AudioDriverKit/IOUserAudioObject/AddCustomProperty",
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# AddCustomProperty

Adds a custom property to the audio object.

```
virtual kern_return_t AddCustomProperty(IOUserAudioCustomProperty *in_custom_property);
```

## Parameters

`in_custom_property`

An [`IOUserAudioCustomProperty`](/documentation/AudioDriverKit/IOUserAudioCustomProperty) object to add to the [`IOUserAudioObject`](/documentation/AudioDriverKit/IOUserAudioObject).

## Return Value

<doc://com.apple.documentation/documentation/DriverKit/kIOReturnSuccess> on success, or another value if an error occurs. For a list of error codes, see <doc://com.apple.documentation/documentation/DriverKit/error-codes>.

## Discussion

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