Audible callouts are only for Terrain and Obstructions, not Airspaces or SUAs. I'd make sure the master volume is up on the main boot up page, at least 50% or more. You can test audio callouts by, entering Simulation Mode under the About->GPS Information menus and Beginning Simulations. If you fly under 800 ft AGL you should get the Red screen for terrain and Terrain Audion callouts "Terrain, Terrain".
Also, there are Threshold setting in the Alerts and Warnings Menus for this. Make sure it is not disabled. You will find the details on these settings and more in the Owners Manual now posted under the Support Tab. I hope this helps.