问Siri实现应用程序由于未被异常而终止应用程序崩溃的原因

EN

1.  
guard let inputNode = audioEngine.inputNode else {
        fatalError("Audio engine has no input node")
    }  
2.  
inputNode.installTap(onBus: 0, bufferSize: 1024, format: recordingFormat) { (buffer, when) in
        self.recognitionRequest?.append(buffer)
}

func getSpeech(asSpeach:String)
{
    print("===================")

    let audioSession  = AVAudioSession.sharedInstance()
    do {
        try audioSession.overrideOutputAudioPort(.speaker)
    } catch {
        print(error.localizedDescription)
    }


    /// <#Description#>
    let synthesizer = AVSpeechSynthesizer()
    let utterance = AVSpeechUtterance(string: asSpeach)
    utterance.rate = AVSpeechUtteranceDefaultSpeechRate
    utterance.volume = 1.0
    utterance.pitchMultiplier = 1.0
    synthesizer.delegate=self
    synthesizer.speak(utterance)

    //        synthesizer.rSpeaking(at: .word)


}