I'd like to listen to Spotify while I am video editing. This is just casual listening - nothing to do with the editing work.

How can I automatically fade out the volume of Spotify when my video editing program plays audio? I often need to hear the video editing audio without the distraction of Spotify playing over the top, but the video editing playback is too on/off/on/off to switch Spotify audio manually each time. Without background music, I get really sick of the repeated playback of the audio clips with only silence inbetween.

I suppose what I needd is an app that monitors sound output from 'App A' and reduces the sound output from all others (Apps B, C, D, etc) when something is played.