@Canageek
Crouton on an ASUS Flip C302c (available in aftersale market) has working audio (under Ubuntu, at least), but only if you install the chroot with factory firmware (power wash) *before* running any updates.
Unlike, say, GalliumOS at boot, which will only screech at you in lieu of audio.
As the device is out of service, you have to set it to Beta mode to force updates to actually happen. Chroot audio installed prior to those updates will continue to work afterwards, so just be sure to keep a current backup of your crouton installation.
That said, presumably Crostini, though not a full dev environment, works with native audio regardless of the hardware.
This, however, became a feature of Chromebooks long after myself became accustomed to crouton. So can't speak to it from personal experience.