play(at:)

Declaration

@MainActor @preconcurrency func play(at time: AVAudioTime) throws

Parameters

• time:

  The AVAudioTime at which the audio resource should start playing.

Discussion

Use this method to schedule playback of a sound source to a precise time in the future. This method enables sample-accurate timing for individual sounds and synchronization of multiple audio sources.

Any call to play() cancels a pending scheduled time and plays audio immediately. Any call to play(at:) cancels a pending scheduled time and reschedules to the new time. The controller ignores calls to play() when audio is already playing.

Audio preparation must complete before the scheduled playback time to maintain precise timing. If preparation is still in progress when the scheduled time arrives, or if the scheduled time is in the past, playback starts immediately, which may result in timing drift. For accurate synchronization, schedule a time sufficiently far in the future.

The isPlaying property becomes true immediately after this call returns. Code that checks isPlaying to decide whether to trigger another action reads the correct state without racing against the scheduled start time.

To synchronize multiple sounds, use the same base time for all scheduled playback calls.