Hi,
Edit: My original post (still listed below) didn't address what you're asking. But, I have something of a workaround, which is a little convoluted, but should get the job done.
Make one "Event Sounds" component and give it any unique name, say "Scene1AudioFade", then, from the "Event To Activate" select "Enable". In the "Enable" method choose "Group Control" for "Action Type", "Fade to Volume" for "Group Command", then select the sound you want fade.
Then, from the "Event To Activate" select "Disable" and this time Select "Fade Out All of Sound".
Then disable the Game Object "Scene1AudioFade".
Now, in the dialogue node that plays the sound add an additional sequence "SetActive(Scene1AudioFade, true)"
and for the node that ends the sequence "SetActive(Scene1AudioFade, false)". You'll probably want to put a delay on the Sequence command that stops the audio for the length of the fade as well. Something like "MAStopAllOfSound(soundGroupName)@1"
(Or, rather than using "SetActive" command, you could use "SetEnabled" and just toggle the single component.) This way you could attach a bunch of trigger components to one game object and keep your scene a little neater!)
Or, much more simply, could you just select "Use Custom Fading" from the "Master Audio Groud" component?
Or is this sound used for multiple events and sometimes its faded and other times not?
Nathan