I can't hear any audio when I play back my converted video or DVD import

This issue is frequently caused when a video is converted with only surround sound and then played back on a laptop (which often doesn't support surround sound). By default iVI will always create a stereo version of any surround sound so it will work on a laptop. You can disable this on the Conversion tab of iVI's preferences but it's not recommended as the video will not have sound on many devices.