This is a question about running Ubuntu on a Chromebook. I've taken this question to /r/chrubuntu and /r/galliumos, and I haven't gotten any help so far. Someone recommended I ask this question at AskUbuntu, so here goes:
I've installed Ubuntu 17.10 under chrx (dual-booting with Chrome OS). Everything seems to be working fine on my system except audio. The system doesn't appear to see my sound card. The only interface I have is
Dummy Audio. arecord -l gives the following:
**** List of CAPTURE Hardware Devices **** card 1: chtrt5650 [chtrt5650], device 0: Audio (*)  Subdevices: 1/1 Subdevice #0: subdevice #0
So, at most it seems my system is only finding the capture card, not the playback device. When logging in from a tty, I get tons of
Audio Port: ASoC: No backend DAIs enabled for Audio Port messages. I've read about some braswell audio issues, and I found reynhout's fixes in Gallium, but from his documentation, they should have been implemented in kernel 4.11 or 4.12. uname -r is
4.13.0-16-generic, so I'm assuming they should already be there. If not, could someone give me some insight as to how to best implement those fixes under Ubuntu 17.10?
The machine is an Acer Chromebook 14 (CB3-431 / EDGAR). I know the sound card isn't dead because it works in Chrome OS.
Thank you in advance for any help you can provide. Cheers!