AI offers this - not guaranteed to be 100% accurate...
"Splitting Audio from Video in PhotoStage
Right-click the video clip in the Media List or on the timeline and select "Unlink Audio" or "Save audio track as a separate file." This separates the audio, placing it on the Narration Track for reuse without video. The extracted audio can then be dragged to the Soundtrack or Narration Track as needed.
Expanding Audio Tracks for Fades
Audio tracks in PhotoStage (Soundtrack and Narration) automatically expand when you drag clips onto them or adjust their length via right-click options like "Trim audio to match slideshow" or "Loop this clip." To add fades, right-click the audio clip directly on the track and choose "Fade In" or "Fade Out" (e.g., for 1 second), or double-click the clip to open the editor where you can drag fade points on the volume line."