# AVAudioSourceNodeRenderBlock A block that supplies audio data to an audio source node. ``` typealias AVAudioSourceNodeRenderBlock = (UnsafeMutablePointer, UnsafePointer, AVAudioFrameCount, UnsafeMutablePointer) -> OSStatus ``` ## Parameters `isSilence` The Boolean value that indicates whether the buffer contains only silence. `timestamp` The HAL time the audio data renders. `frameCount` The number of sample frames of audio data the engine requests. `outputData` The output data. ## Return Value An `OSStatus` result code. When returning an error, consider the audio data invalid. ## Discussion --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)