Acer CB315-H2 (ALEENA) no sound on Debian12

Hi !
I just have a fresh install of Debian12 on my Acer CB315-H2 Chromebook,
it has the ALEENA board version, it’s a AMD chipset laptop
Everything works great, with the exception of SOUND. I only get a dummy output.

In Alsamixer, I do get audio drivers (but they seemed to be the HDMI ones)

Newbie in Linux in general, I’ve ran the WierdTreeThings sript, without success in making sound work on the laptop. I also searched for anything related to the ALEENA board, but haven’t found something that works (and most of the info is already a few years old),

Anyone has got audio to work on this? Any help would be much appreciated