我尝试使用AudioKit v5.6.1从麦克风读取，但我很难设置AudioEngine的输入设备.我正在测试运行iOS 16.4和Xcode v14.3的iPhone 12 mini.这里是我测试的代码：import Foundation导入AudioKit

public class AudioService {
    
    public static let instance = AudioService()
    
    private let engine: AudioEngine
    
    private init () {
        
        engine = AudioEngine()
        
        guard !engine.avEngine.isRunning else {
            print("Audio engine is already running")
            return
        }
        
        guard case let inputs = AudioEngine.inputDevices, inputs.isNotEmpty else {
            print("Could not find any input devices")
            return
        }
        
        let input = inputs[0]
        
        try! AudioEngine.setInputDevice(input)
        
        
    }
}

我只是在View中初始化此服务：

import SwiftUI

struct TestView: View {
    
    let audioService = AudioService.instance
    
    var body: some View {
        ...
    }
}

然而，当我调用AudioEngine.setInputDevice时，我收到了这个错误Foundation._GenericObjCError.nilError，但已经确认input不是nil。它有name = "iPhone Microphone"和deviceID = "Built-In Microphone Bottom"。任何帮助都将不胜感激，因为查看AudioKit食谱，我看不出我可以做什么不同的事情。