Is something like playBackgroundSound(null) possible?

Or is it better to playSound("silence") to end all current sounds (with a short "silent" wav file)?

There's no solution for this for now. I'll think about it quickly.

Thanks for the fast response!

Either option is fine by me; obviously the first ("null") would be "cleaner" but if using a workaround like the second option (i.e. a second calling of playBackgroundSound stops a previous one and starts the new one right away) is easier, that would be fine too.

The next release will include API 4, which itself include : null in order to stop all sounds