Actually I got the idea regarding the callStatusListener, and how it works already. Also when I need to play sound, where I need to put the code for playing sound etc.
But the problem is when I call SoundControl.getInstance(), it results in an error in ConfigurationLoader.js.
[ me.configLoadedListener.apply(this, [me.configuration]); --> Cannot call apply of undefined]..
So guessing I'm doing something wrong