This SourceBuffer has been removed from the parent media source

Question

I'm trying to readStream an mp4 file and send chunks back to the client. I'm using the mediasource api. The code is failing on:

 sourceBuffer.appendBuffer(new Uint8Array(mediaChunkBuffer));

with the error: This SourceBuffer has been removed from the parent media source

I'm able to append the first chunk this is done by calling initialMediaChunk(). for all subsequent chunks, i'm calling subsequentMediaChunk(). I get a MediaSource Api error.

I notice after the first chunk, the mediaSource sourceclose event is called, making the mediaSource.readystate set to false, for subsequent chunks.

let mediaSource;
let mediaQueue = [];
let mediaChunkBuffer; 

function subsequentMediaChunk(dataObj)
{
    mediaChunkBuffer = new Uint8Array(dataObj.data.dataChunk).buffer;
    if (sourceBuffer.updating || mediaQueue.length > 0) {
        mediaQueue.push(mediaChunkBuffer);
    } else {
        sourceBuffer.appendBuffer(new Uint8Array(mediaChunkBuffer));  // failing here
    }
}
function initialMediaChunk(dataObj){
    mediaChunkBuffer = new Uint8Array(dataObj.data.dataChunk).buffer;
    var mimeCodec = 'video/mp4; codecs="avc1.42E01E, mp4a.40.2"';

         if ('MediaSource' in window && MediaSource.isTypeSupported(mimeCodec)) {
         mediaSource = new MediaSource();
         mediaSource.addEventListener('error', function(e) {
         console.log(e);
         });
         mediaSource.addEventListener('sourceclose', function(e) {
         console.log(e);
         })
         mediaSource.addEventListener('sourceopen', function(e) {
             var mime = 'video/mp4; codecs="avc1.42E01E, mp4a.40.2"';
             sourceBuffer = mediaSource.addSourceBuffer(mime);

             var file = new Blob([mediaChunkBuffer], {type: type});
             var reader = new FileReader();

              reader.onload = function(e) {
                sourceBuffer.addEventListener('onupdate', function() { // Note: Have tried 'updateend'
                    if (mediaQueue.length > 0 && !sourceBuffer.updating) {

                      sourceBuffer.appendBuffer(new Uint8Array(mediaQueue.shift()));
                    }
                });
                sourceBuffer.appendBuffer(new Uint8Array(e.target.result));
              }

              reader.readAsArrayBuffer(file);

          }, false);
         let videoElement = $("#" + loadVideoFileName).find('video');
         videoElement.attr("src",window.URL.createObjectURL(mediaSource));

       }
}