I'm trying to setup a simple rotation of a 3D sound around a listener in iOS 12.3.1 using the AVAudioFramework. The idea is to have a listener in the center, a sound at 10m distance form the listener, and then rotate the listener. I can get the sound to play, but not as spatial sound. Can someone point me where the problem might be ? Here is my code so far: import UIKit import AVFoundation class ViewController: UIViewController { var engine: AVAudioEngine! var player: AVAudioPlayerNode! var environment: AVAudioEnvironmentNode! private var currentYaw: Float = 0 private var rotationSpeed: Float = 50.0 / 60.0 // 50 degrees per second, divided by 60 to get per frame at 60Hz private var timer: Timer? override func viewDidLoad() { super.viewDidLoad() engine = AVAudioEngine() player = AVAudioPlayerNode() environment = AVAudioEnvironmentNode() guard let fileURL = Bundle.main.url(forResource: "hello", withExtension: "wav") else { fatalError("Could not find audio file!") } do { let audioFile = try AVAudioFile(forReading: fileURL) // Check the format of the audio file. print("File format: \(audioFile.fileFormat)") print("Processing format: \(audioFile.processingFormat)") engine.attach(player) engine.attach(environment) let stereoFormat = AVAudioFormat(standardFormatWithSampleRate: audioFile.fileFormat.sampleRate, channels: 2)! // Connect player to environment node and then to the main mixer using stereo format engine.connect(player, to: environment, format: stereoFormat) engine.connect(environment, to: engine.mainMixerNode, format: stereoFormat) // Set the rendering algorithm on the environment node environment.renderingAlgorithm = .HRTFHQ // Position the player at the centre if let positionalPlayer = player as? AVAudio3DMixing { positionalPlayer.position = AVAudio3DPoint(x: 0, y: 0, z: 0) } // Position the sound 10m in front of the center if let positionalEnvironment = environment as? AVAudio3DMixing { positionalEnvironment.position = AVAudio3DPoint(x: 0, y: 0, z: 10) } player.scheduleFile(audioFile, at: nil, completionHandler: nil) engine.prepare() try engine.start() player.play() // Start the timer to update the listener's orientation timer = Timer.scheduledTimer(timeInterval: 1.0/60.0, target: self, selector: #selector(updateListenerOrientation), userInfo: nil, repeats: true) } catch let error { fatalError("Error: \(error.localizedDescription)") } } @objc func updateListenerOrientation() { // Update yaw currentYaw -= rotationSpeed if currentYaw < -360 { currentYaw += 360 } // Set the updated yaw to the listener's orientation environment.listenerAngularOrientation = AVAudio3DAngularOrientation(yaw: currentYaw, pitch: 0, roll: 0) // Print the updated value for debugging print("Updated listenerAngularOrientation:", environment.listenerAngularOrientation) } deinit { timer?.invalidate() } }