Sydney theme icons

I have installed, uninstalled and installed Sydney 1.12 so man times. It’s frustrating.
I see in the stylesheets that there is coding for social media…..where are the icons? Nowhere in Customizer or in Settings?

Also, where are the Services icons? In other themes, when you add a theme widget ir section, the icons are a settings option.

Please asvise ASAP.

Also, an FYI, your YouTube videos have no audio. I’ve listened on 3 devices and 3 browsers and niente ??