Version 21.09 is available upstream. Please consider updating!
It seems that version 21.09 is available upstream, while the latest version in the Gentoo tree is 21.01. You think this warning is false? Read more about it here.
FAudio, is an XAudio reimplementation that focuses solely on developing fully accurate DirectX Audio runtime libraries
for the FNA project, including XAudio2, X3DAudio, XAPO, and XACT3.
Project Website: http://fna-xna.github.io/