訪問麥克風後，整個應用的音量變得更低噪音

Question

我在我的iOS應用中遇到了音量問題。當我撥打setupMic()時，整個應用的音量水平顯着降低。
這裏是我使用的代碼：

func setupMic() { 
    //make an AudioSession, set it to PlayAndRecord and make it active 
    let audioSession: AVAudioSession = AVAudioSession.sharedInstance() 
    do { 
     try audioSession.setCategory(AVAudioSessionCategoryPlayAndRecord) 
    } catch { 
     print("There was an error setting the category") 
    } 
    do { 
     try audioSession.setActive(true) 
    } catch { 
     print("There was an error setting the audio session to active") 
    } 


    //set up the URL for the audio file 
    let documents: AnyObject = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)[0] 
    let str = documents.stringByAppendingPathComponent("recordTest.caf") 
    let url = NSURL.fileURLWithPath(str as String) 

    //make a dictionary to hold the recording setting so we can instantiate our AVAudioRecorder 
    let number = NSNumber(unsignedInt: kAudioFormatAppleIMA4) 
    let recordSettings: [String: AnyObject] = [AVFormatIDKey: number, 
               AVSampleRateKey: 44100.0, 
               AVNumberOfChannelsKey: 2, 
               AVEncoderBitRateKey: 12800, 
               AVLinearPCMBitDepthKey: 16, 
               AVEncoderAudioQualityKey: AVAudioQuality.Min.rawValue] 

    //Instantiate an AVAudioRecorder 
    do { 
     recorder = try AVAudioRecorder(URL: url, settings: recordSettings) 
    } catch { 
     print("There was an error") 
    } 
} 

//This function is called everytime our timer levelTimer fires 
func levelTimerCallback() { 
    recorder.updateMeters() 
    let averagePower = self.recorder.peakPowerForChannel(0) 
    if averagePower > -7 { 
     stopMonitoring() 

     print(recorder.peakPowerForChannel(0)) 
     didCompleteChallenge(true) 
    } 
} 

func startMonitoring() { 
    if self.recorder != nil { 
     recorder.prepareToRecord() 
     recorder.meteringEnabled = true 
     //start recording 
     recorder.record() 
     //instantiate a timer to be called with whatever frequency we want to grab metering values 
     self.levelTimer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: #selector(levelTimerCallback), userInfo: nil, repeats: true) 
    } 
} 

func stopMonitoring() { 
    self.recorder.stop() 
    self.recorder.deleteRecording() 
    self.levelTimer.invalidate() 
} 

我打電話setupMic()和startMonitoring()在updateWith()方法。當視圖更新爲updateWith() 時，我還會撥打stopMonitoring()一旦麥克風被訪問，音量就會下降。有什麼建議麼？任何修復？

Answer 1

修復了這個問題。音量實際上沒有變得更安靜，音頻實際上是路由到耳機。我只需要將音頻會話類別選項設置爲.DefaultToSpeaker。 AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayAndRecord, withOptions: [.DefaultToSpeaker])。無論如何，互聯網。