iOS Swift - 使用蓝牙外置扬声器时音质不佳

Question

我正在使用从 url 流式传输的 iOS 应用程序( radio 应用程序)，一旦我尝试通过蓝牙设备(如外部扬声器或汽车音响系统)从应用程序流式传输，音频质量非常差且刺耳。从 iOS 设备本身播放时，一切听起来都不错(扬声器和耳机)。

    override func viewDidLoad() {
    super.viewDidLoad()


    // Set AVFoundation category, required for background audio
    var error: NSError?
    var success: Bool


    do {

        try AVAudioSession.sharedInstance().setCategory(
            AVAudioSessionCategoryPlayAndRecord,

            withOptions: [
                AVAudioSessionCategoryOptions.AllowBluetooth,
                AVAudioSessionCategoryOptions.DefaultToSpeaker])
        success = true
    } catch let error1 as NSError {
        error = error1
        success = false
    }

    if !success {
        print("Failed to set audio session category.  Error: \(error)")
    }

Answer 1

感谢 Michal Cichon 的评论，这段代码终于对我有用，蓝牙也没有失真

        do{
            if #available(iOS 10.0, *) {
                try AVAudioSession.sharedInstance().setCategory(.playAndRecord, 
                mode: .default, options: [.mixWithOthers, .allowAirPlay, 
                .allowBluetoothA2DP,.defaultToSpeaker])
                print("ios 10 and above")

            } else {
                 print("ios 10 and lower")
                let options: [AVAudioSession.CategoryOptions] = 
                [.mixWithOthers, .allowBluetooth]
                let category = AVAudioSession.Category.playAndRecord
                let selector = 
                NSSelectorFromString("setCategory:withOptions:error:")
                AVAudioSession.sharedInstance().perform(selector, with: 
                 category, with: options)
            }

            try AVAudioSession.sharedInstance().setActive(true)
            captureSession.automaticallyConfiguresApplicationAudioSession = 
                false
         }