private async void DumpButton_Click(object sender, RoutedEventArgs e)
        {
            await _captureManager.StopRecordAsync();

            var data = new byte[_stream.Length];
            await _stream.ReadAsync(data, 0, data.Length);

            var storageFolder = ApplicationData.Current.LocalFolder;
            var sampleFile    = await storageFolder.CreateFileAsync("test.mp4", CreationCollisionOption.ReplaceExisting);

            await FileIO.WriteBytesAsync(sampleFile, data);
        }