Issues handling audio fades between levels


I’m working on a game where we’re having issues with getting the appropriate sound classes to fade in/out the audio between levels.
We can’t fade out the global volume level as in some instances we don’t want to fade out the music nor some of the other sound classes.

Ideally we’d like to be able to select which soundclasses are included/excluded and be able to set the appropriate fade times for them.

How are people handling audio fades between levels? Has anybody used sound mixes for this? If so, how are these set up?