Stopping Soundscape sounds

In my setup I am using the Soundscape Subsystem to play ambient sounds around the player. All is working well, however, I want to be able to cutoff the sounds from playing immediately. I have an event that basically clears the state but the sounds continue to play for the duration of the sound. Once done they do not play again as I want.

How can I stop a sound mid duration? The sound files (cue and Meta) are in the palette and color of the Soundscape System. To me it does not look like Soundscape has this functionality built in. Any work around I may be overlooking?