You don't say how you are recording these sounds.

If your soundtrack is clipping as it is being recorded, then it will always crackle when you export it.

Take care to get your audio into your NLE in as clean a way as possible. Preferably using a separate audio recording device. Watch those input levels. This will make mixing and exporting much easier.

imho.

Even mis-matched impedences due to plugging the wrong sort of audio equipment into a 'mic' socket can degrade your audio.