我正在尝试使用2个AVPlayer实例播放多个音频文件，但是其中一个播放器停止了几分之一秒，而不是同时播放所有音频文件。该程序的逻辑如下：

var player: AVPlayer?将从我的数据库流式传输音频文件。就其本身而言，玩起来很完美。

fileprivate var countPlayer: AVPlayer?播放当前正在播放的项目的计数var player。计数是一个1到8的序列，对于每个数字，我正在本地存储/设置一个.wav文件，例如1.wav，2.wav … 8.wav。

当的当前时间var player是某个时间时，将countPlayer被触发并播放本地文件1.wav，2.wav..etc中的一个。

问题在于，当var countPlayer开始播放时，它会导致后台AVPlayer var player停止播放一秒钟，类似于此注释中所述：

   var player: AVPlayer? //plays the song
   fileprivate var countPlayer: AVPlayer?  // plays the count number of song



   private func addBoundaryTimeObserver(tableIndexPath: IndexPath) {


    let mediaItem = mediaArray[tableIndexPath.row]

    guard let url = URL(string: mediaItem.mediaAudioUrlStringRepresentation ?? "") else {return}
    let playerItem = AVPlayerItem(url: url)
    player = AVPlayer(playerItem: playerItem)

    var timesToTransverse = [NSValue]()

    //convert string representation of times elements to array
    let timesRecorded: [String] = mediaItem.timesRecorded.components(separatedBy: ",")

    // Build boundary times from arrayOfBeats keys
    let timeDoubles: [Double] = timesRecorded.compactMap {timeString in
        if let second = Double("\(timeString)") {
            return second
        }
        return nil
    }

    guard timeDoubles.count > 0 else {return} //unexpected

     timesToTransverse = timeDoubles.map { second in
        let cmtime = CMTime(seconds: second, preferredTimescale: CMTimeScale(NSEC_PER_SEC))
        return NSValue(time: cmtime)
    }

    guard timesToTransverse.count != 0 else {return}

        guard let playerCell = tableView.cellForRow(at: IndexPath(row: 0, section: 0)) as? PlayerCell else {return}

       startTime = Date().timeIntervalSinceReferenceDate

    timeIndex = 0
    player?.play()
    player?.rate = Float(initialPlaybackRate)



    // find the index of time
    //reset timeObserverToken
    // call a function with the new times sorted


    // Queue on which to invoke the callback
    let mainQueue = DispatchQueue.main
    // Add time observer
    timeObserverToken =
        player?.addBoundaryTimeObserver(forTimes: timesToTransverse, queue: mainQueue) {
            [weak self] in


            //because there are no time signature changes, we can simply increment  timeIndex with + 1 every time `addBoundaryTimeObserver` completion handler is called and subscript timesToTransverse with timeIndex in order to get the subsequent timeInSeconds
            guard let strongSelf = self, strongSelf.timeIndex < timesToTransverse.count else {return}

            let timeElement = timesToTransverse[strongSelf.timeIndex]
            strongSelf.timeInSeconds = CMTimeGetSeconds(timeElement.timeValue)

                //show progress in progressView
                let duration = CMTimeGetSeconds(playerItem.duration)
                let cmtimeSeconds = CMTime(seconds: strongSelf.timeInSeconds, preferredTimescale: CMTimeScale(NSEC_PER_SEC))

            //Total time since timer started, in seconds
            strongSelf.timeInSeconds = Date().timeIntervalSinceReferenceDate - strongSelf.startTime

            let timeString = String(format: "%.2f", strongSelf.timeInSeconds)
            strongSelf.timeString = timeString


            //use reminder operator to determine the beat count
            let beat = (strongSelf.timeIndex + 1) % 8 == 0 ? 8 : ((strongSelf.timeIndex + 1) % 8)


            //play the beat count : 1, 2, ...8
          self.preapareToPlayAudio(beatCount: beat)

            /*
             0: (0 + 1) % 8 = 1
             1: (1 + 1) % 8 = 2
             6: (6 + 1) % 8 = 7
             7: (7 + 1) % 8 = 0
             */

            strongSelf.timeIndex += 1
    }
}//end addBoundaryTimeObserver


 //prepare determine what wav file to play 
   private func preapareToPlayAudio(beatCount: Int) {

  switch beatCount {  
    case 1:
        guard let url = Bundle.main.url(forResource: "1", withExtension: "wav") else {return}
        playWith(beatCountURL: url)

        //7 more cases go here .....
    default: print("unexpected case here")
    }   
}//end play(beatCount: Int)



     private func playWith(beatCountURL: URL) {

        let playerItem = AVPlayerItem(url: beatCountURL)
        countPlayer = AVPlayer(playerItem: playerItem)
        countPlayer?.play()
      }