Yes, you can customize the audio track in your video. Here's how you do it:
1) Click on the Audio Track options button
To change the audio track, click on the button with the music icon on the bottom left of the Video Editor.
If you haven't yet set the custom audio, it will show the information of the stock audio provided with the video design. Click on the 'Use Custom Audio Track' button to change the audio.
2) Select & add your audio file
Here you can select an audio file you want to use, and add it to your video.
3) Trim the audio
Select the part of the audio track you'd like to use for your video. The length of the audio you can use equals the total duration of the video.
4) Custom Audio Has Been Applied!
Once the audio track is uploaded, the 'Custom' label will be displayed next to the music icon. This means your audio file has been applied to your video! Now finish making your video as usual, and you'll hear the audio you've selected when you play the video.
* When you add a custom audio file, it should be at least 1~2 second longer than the template length as the system requires a "bumper" to avoid any kind of rendering issues
* You can only use audio tracks you created yourself, or have a commercial license that allows video usage. You cannot use musics from sites like iTunes Music Store or YouTube downloader sites.
* Keep in mind that when you change the audio track of a video, you're solely responsible for any potential copyright infringement complaints (A social media platform could block your video due to copyright issues). If you want to be 100% sure about using commercially licensed music, you're free to keep the original audio track.