The Steam Link audio drivers for Windows 8.1 and 10 PCs, hosted here since I couldn't find an official Valve download for them.
If you're unaware, Steam Link is a feature that allows the real-time playing of your Steam Library to and from various platforms. The audio drivers are typically installed on the first stream and any subsequent streams. One thing that seems to have gone relatively unnoticed about them is that at their core, the Steam Streaming Microphone and Steam Streaming Speakers are both functionally drop-in replacements for any existing Virtual Audio Cable setup, and it's FREE! This is the backbone of my Soundboard.
Installation is simple, just right click the .inf files and click "Install".
If Valve comes across this and gets upset at me for publishing their shit without permission, that's understandable. A lot of hard work probably went into making this, and I'm not looking to discredit the fine folks who made this beauty. I'll be perfectly happy to remove this upload if requested - once a prominent publicly accessible download link for these files is placed on the Steam Link support site. Seriously guys, I got lucky by having a laptop with a functioning copy of the drivers on it. Not everyone has that luxury. This should be something that's easy to find since you offer it for free.
All credit goes to Valve software.