Videos with cracking sound after exporting from Movie Maker

I am merging around 12 clips of videos into a single one. I had added a caption as part 1, part 2, etc. on the front. Now this videos are based on a video tutorial. I had used a online screen recording software. All recorded videos are saved in MP4 format with HD resolution. I imported them in Movie Maker that took really long time. But the audio quality is very bad. I am not able to figure out why Movie Maker is just spoiling the audio quality. While the video is fine. It is not having any problem.

Looks like the videos are not encoded properly. Here before adding them directly in Movie Maker just download a good video convertor software. Import your clips in it and then convert them in a readable format. This will automatically fix the audio quality. Import those files in movie maker and then check back. I am quiet sure that will surely resolve the issue. You can use Total Video Convertor. This is a simple to use software which has settings to boost the audio quality. Just check that once.

If the above process does not work then you have to create mp3 audio files from those videos. You can add them later on in movie maker. The same video convertor software will also help you to generate audio files from the videos. You can boost the volume and make it more clear through a good sound editor software. Then import the video files in Movie Maker and reduce the volume to 0. Then import the audio files and add them one by one on all videos. Create the movie and done.