"Valve", "Steam" and the associated figurative images as well as derivatives thereof, such as "Steam Audio", (collectively: the "Valve Marks") are trademarks and/or registered trademarks of Valve Corporation in the US and in various other jurisdictions. All rights reserved.
The Steam Audio code base is provided under an Apache 2.0 license. That means that you do not receive a license to the Valve Marks, either as word marks or as figurative marks. Rather, Valve grants permission to use the Valve Marks as required for reasonable and customary use in describing the origin of the Steam Audio code base.
In particular, you must not use the Valve Marks in a way that may imply an endorsement by, or affiliation with, Valve Corp.
More information on the proper use of the Valve Marks can be found at https://partner.steamgames.com/doc/marketing/branding