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# init(track:)

Creates a mutable input parameters object for a given track.

```
convenience init(track: AVAssetTrack?)
```

## Parameters

`track`

The track to associate with the input parameters object.

## Return Value

A mutable input parameters object with no volume ramps and [`trackID`](/documentation/AVFoundation/AVMutableAudioMixInputParameters/trackID) set to `track`’s identifier.

## Discussion

---

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