For the second time today, I’m trying to use SoundSet Creator and can’t get any sounds to play. It wasn’t working early this morning, then started working for a while, and now isn’t again.
I’m using Chrome on a Mac. My sound is working fine on other programs and on the Syrinscape Mac OS program, just not the SoundSet Creator.
You always need to have the Online Player open if you want to be able to hear sounds, the Creator and Master interface are just that, UI’s to enable you to build and control sounds. The actual Player is required to play the sounds 
@jaypinjax @Steve We’ve just rolled out an update that hopefully makes this really obvious. If you attempt to access the master interface without an active Syrinscape Online Player connected, the master interface will be blacked out with an alert that says
Audio playback is unavailable. You have no active Syrinscape Online (beta) Player connected. Download for Windows, macOS, iOS, or Android.
We previously had a similar alert that only showed up when you had no active device (connected or not), and the alert was dismissible, and the master interface still accessible.