I have an AVAudioPlayer that fades in from silence over 3 seconds. To accomplish that, before creating the player I set its volume to 0, start it, then immediately set the fadeDuration:

somePlayer.setVolume(0.0, fadeDuration: 0.0) 
somePlayer.play()
somePlayer.setVolume(1.0, fadeDuration: 3.0)

Works great.

I would like the ability to fade the player back to 0.0 before it's completed fading up; for example if a track is fading in and the user changes their mind, they can immediately "stop" it and it will fade back out cleanly. However, when I call

somePlayer.setVolume(0.0, fadeDuration: 3.0)

on that same AVAudioPlayer instance it "jumps" all the way to 1.0 before starting to fade out, as if the method just ran the entire fade-in instantly.

Is there a way to prevent that "jump" from happening? Running it through something like AVAudioEngine won't work, as I'm looking to create multiple tracks that can individually be faded in and out.

Thanks!