问如何从iPhone 11或iPhone 11专业版Max获得采样率为44100的音频

EN

let audioEngine = AVAudioEngine()
    let inputNode = audioEngine.inputNode
    let main = audioEngine.mainMixerNode
    let inputFormat = inputNode.inputFormat(forBus: 0)
    let outputFormat = AVAudioFormat(commonFormat: AVAudioCommonFormat.pcmFormatInt16, sampleRate: 44100, channels: 1, interleaved: true)
    audioEngine.attach(downMixer)
    audioEngine.connect(inputNode, to: downMixer, format: inputFormat)
    audioEngine.connect(downMixer, to: main, format: outputFormat)
    downMixer.installTap(onBus: 0, bufferSize: 2048, format: outputFormat) { (buffer, time) -> Void in
        print(buffer)
    }