Error writing audio to android using getUserMedia "js"

This code below is from a web page that makes audio recording. I have a problem that I can not solve already tried several ways and nothing ... The problem is the following when I squeeze the code on a desktop it works normal, the audio comes out clean the real problem happens when I do the same test in android "6.0 , 7.0 ", it manages to do the whole process but the audio comes out with a voice failing, already tried to correct more I can not. Maybe someone who already has more experience can help me.

NOTE: I use "https" on the page.

      var audioContext = null;
      var context = null;
      var volume = null;
      var audioInput = null;
      var recorder = null;
      var recordingLength = 0;
      var leftchannel = [];
      var rightchannel = [];
      var bufferSize = 2048;
      var sampleRate = 48000;
      var requestStreamReadPermission = {
          audio: true
      };
      $scope.canRecordAudio = false;

      // -
      navigator.getUserMedia = (navigator.getUserMedia ||
        navigator.webkitGetUserMedia ||
        navigator.mozGetUserMedia ||
        navigator.msGetUserMedia);

      // -
      var writeUTFBytes = function(view, offset, string) {
        var lng = string.length;
        for (var i = 0; i < lng; i++) {
          view.setUint8(offset + i, string.charCodeAt(i));
        }
      };

      // -
      var interleave = function(leftChannel, rightChannel) {

        var length = leftChannel.length + rightChannel.length;
        var result = new Float32Array(length);

        var inputIndex = 0;

        for (var index = 0; index < length;) {
          result[index++] = leftChannel[inputIndex];
          result[index++] = rightChannel[inputIndex];
          inputIndex++;
        }
        return result;

      };

      // -
      var mergeBuffers = function(channelBuffer, recordingLength) {
        var result = new Float32Array(recordingLength);
        var offset = 0;
        var lng = channelBuffer.length;
        for (var i = 0; i < lng; i++) {
          var buffer = channelBuffer[i];
          result.set(buffer, offset);
          offset += buffer.length;
        }
        return result;
      };

      // -
      var errorGetUserMedia = function(error) {
        console.log(error);
        GeneralMessageService.clean();
        GeneralMessageService.addMessage($filter('translate')('chat.mobile.checkorwaitforconnection'));
      };

      // -
      var successGetUserMedia = function(stream) {

        audioContext = window.AudioContext || window.webkitAudioContext;
        context = new audioContext();
        // recupera a taxa de amostragem atual a ser usada para a embalagem WAV
        sampleRate = context.sampleRate;
        volume = context.createGain();
        audioInput = context.createMediaStreamSource(stream);
        audioInput.connect(volume);
        //recorder = context.createScriptProcessor(bufferSize, 2, 2);
        var numberOfInputChannels = 2;
        var numberOfOutputChannels = 2;
        if (context.createScriptProcessor) {
            recorder = context.createScriptProcessor(bufferSize, numberOfInputChannels, numberOfOutputChannels);
        } else {
            recorder = context.createJavaScriptNode(bufferSize, numberOfInputChannels, numberOfOutputChannels);
        }

        recorder.onaudioprocess = function(stream) {

          if (!$scope.recordingAudio) {
            return;
          }
          var left = stream.inputBuffer.getChannelData(0);
          var right = stream.inputBuffer.getChannelData(1);

          leftchannel.push(new Float32Array(left));
          rightchannel.push(new Float32Array(right));
          recordingLength += bufferSize;

        };

        volume.connect(recorder);
        recorder.connect(context.destination);

        $scope.canRecordAudio = true;

      };

      // -
      if (!!navigator.getUserMedia) {
        navigator.getUserMedia(
          requestStreamReadPermission,
          successGetUserMedia,
          errorGetUserMedia
        );
      } else {
        errorGetUserMedia('UserMedia is empty');
      }

      // -
      var startRecording = function() {
        leftchannel.length = rightchannel.length = 0;
        recordingLength = 0;
      };

      // -
      var stopRecording = function() {

        var leftBuffer = mergeBuffers(leftchannel, recordingLength);
        var rightBuffer = mergeBuffers(rightchannel, recordingLength);
        var interleaved = interleave(leftBuffer, rightBuffer);
        var buffer = new ArrayBuffer(44 + interleaved.length * 2);
        var view = new DataView(buffer);

        writeUTFBytes(view, 0, 'RIFF');
        view.setUint32(4, 44 + interleaved.length * 2, true);
        writeUTFBytes(view, 8, 'WAVE');
        writeUTFBytes(view, 12, 'fmt ');
        view.setUint32(16, 16, true);
        view.setUint16(20, 1, true);
        view.setUint16(22, 2, true);
        view.setUint32(24, sampleRate, true);
        view.setUint32(28, sampleRate * 4, true);
        view.setUint16(32, 4, true);
        view.setUint16(34, 16, true);
        writeUTFBytes(view, 36, 'data');
        view.setUint32(40, interleaved.length * 2, true);

        var lng = interleaved.length;
        var index = 44;
        var volume = 1;
        for (var i = 0; i < lng; i++) {
            var s = Math.max(-1, Math.min(1, interleaved[i]));
            view.setInt16(index,  s < 0 ? s * 0x8000 : s * 0x7FFF, true);
          index += 2;
        }

        var blob = new Blob([view], {
          type: 'audio/mp3'
        });
        var url = (window.URL || window.webkitURL).createObjectURL(blob);

        addAudioMessage(url);
        clear();

      };

      function clear(){
        recordingLength = 0;
        leftchannel = [];
        rightchannel = [];
      }