Safari blocks media with sound by default. You can change that by updating a simple parameter:
1. In your Safari browser window, on the top, click on Safari > Preferences
2. On the top menu, navigate to the tab Websites and on the right hand-side, select Auto-Play
3. Click on the drop-down menu next to 'When visiting other websites' and select the option 'Allow All Auto-Play'.
You should now be able to play and hear all the media available in the simulations.
Alternatively, you can use any other of our supported browsers.