When you open a multimedia file that contains both audio and video, these two parts stay connected, even though they are in separate lists. Some commands are affected by the link, while others aren't, as described below:

1. Clicking on a video file automatically highlights its linked audio.
2. Deleting the video part deletes its audio as well (and vice versa). To delete an item independently use the Delete Unlinked command.
3. Changing in/out points of a video file automatically adjusts in/out points of the linked audio file (and vice versa). To unlink audio and video click Edit > Unlink.
4. Moving a video part up/down in the list does not move its linked audio.