After creating a video, I post-process the audio in specialist software to remove clicks and hiss.
I then use video editing software to replace the original audio track with the cleaned one.
(This is something that I could do in AP as I can import the video into a blank slide, mute the original sound and then import the cleaned audio)
However it would be useful if the cleaned audio could be imported back into the original pre-rendered project and automatically split at the end of the existing slides based on the pre-existing durations.
This would also be useful for people wanting to add background music.