Why are my videos muted by default?
If you notice that the videos are muted by default, this is a browser specific setting. Unfortunately we don't have the ability to override local browser settings, however you can enable audio in your own settings. Once audio is enabled in your browser or for your site, this setting will apply going forward, so you should only have to adjust these settings once in your browser.
Here are some helpful instructions for adjusting browser settings:
How to Allow or Block Sites to Play Sound in Google Chrome
What to Do If Firefox Won't Play Any Sounds
Allow All Auto-Play in Safari (this will allow autoplay videos with sound to play)
How do I turn closed captioning on and off?
Hold cursor over the screen and the navigation bar appears. The CC inside the box has the options. Click Off to turn it off. Click English to turn it on.