Troubleshoot for no audio output

Hi. Can't figure out why I have no audio output.,here is what IS working ( Scarlett 8i6):
-The interface is the default computer record and playback device and the "test" works
-it's shown as the interface in the preferences menu.
- it records tracks
 
You get the picture.. but no audio playback. The master bus meter is showing the signal. My guess is, it's a simple thing I miss.
 
 
 

And which checkbox was it?