# AudioQueuePrime(_:_:_:) Decodes enqueued buffers in preparation for playback. ``` func AudioQueuePrime(_ inAQ: AudioQueueRef, _ inNumberOfFramesToPrepare: UInt32, _ outNumberOfFramesPrepared: UnsafeMutablePointer?) -> OSStatus ``` ## Parameters `inAQ` The audio queue to be primed. `inNumberOfFramesToPrepare` The number of frames to decode before returning. Pass `0` to decode all enqueued buffers. `outNumberOfFramesPrepared` On output, the number of frames actually decoded and prepared for playback. Pass `NULL` on input if you you are not interested in this information. ## Return Value A result code. See Result Codes. ## Discussion This function decodes enqueued buffers in preparation for playback. It returns when at least the number of audio sample frames specified in `inNumberOfFramesToPrepare` are decoded and ready to play, or (if you pass `0` for the `inNumberOfFramesToPrepare` parameter), when all enqueued buffers are decoded. To make a buffer of audio data ready to play, use [`AudioQueuePrime(_:_:_:)`](/documentation/AudioToolbox/AudioQueuePrime(_:_:_:)) as follows: 1. Call [`AudioQueueEnqueueBuffer(_:_:_:_:)`](/documentation/AudioToolbox/AudioQueueEnqueueBuffer(_:_:_:_:)). 2. Call [`AudioQueuePrime(_:_:_:)`](/documentation/AudioToolbox/AudioQueuePrime(_:_:_:)). 3. Call [`AudioQueueStart(_:_:)`](/documentation/AudioToolbox/AudioQueueStart(_:_:)). --- 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)