Latitude 9520, sound in liveUSB, no sound once installed!

Hi,

Soooo, I’m trying to migrate my Latitude 9520 from Kubuntu to EOS (it was my last Debian-based machine)

I know sound is a problem on that machine, cf No sound from speakers on fresh install - #62 by Gamall . So it test it in live, and on the recent images, sound works. Sound input and output detected as “Tiger Lake-LP Smart Sound Technology Audio Controller xyz”.

So I install it on disk (KDE), reboot… and no sound devices detected !

(rant: What is the bloody point of having live USBs if you can’t rely on them to test whether your hardware works? Had I known sound wouldn’t work I would not have done this today!)

What does the installed environment do differently from the live one, wrt sound ? Is there a way to rerun whatever script the live USB environment did ?

WTF ?

I reinstalled, for unrelated reasons (I wanted an unencrypted initramfs; I screwed that up a bit, actually), and lo and behold, the first thing I see upon booting is that I have sound.

What is going on, that whether my sound hardware is detected seems random ? I’m flummoxed. Glad to have sound, but still… :confused: