I don't know and I won't spend time investigating. We cannot provide support for 3rd party images/software.
Moved to off-topic since OP is not using Armbian.
If the armbian-install way does not work, you can also write the image directly to the ssd, either with a different computer or, since you were already successfully booting from usb, download the image again and dd it to the ssd. No need to do partitioning beforehand, just write to the raw device since the image already contains the partition table iirc.
Yes, current broke at some point. More up to date packages should be available via apt.
In general the support for rk3588 in 6.12 (current as of today) is barely there but there won't be updates regarding that matter, bug fixes only due to its LTS nature. Better use vendor or edge.
I think there are some userspace drivers needed as well. Armbian provides the kernel module only. Not exactly sure what's needed but I think the stuff is from here: https://github.com/airockchip/rknn-toolkit2/tree/master/rknpu2
I see.
Well there is a similar topic, maybe this can give some clues: https://forum.armbian.com/topic/50228-i2s-audio-not-working-on-orange-pi-zero-2w-allwinner-h618-with-max98357a/
Looks like that one can take stereo input but it is mostly designed to output one channel only.
Did not research on my own but asked LLM. Since you experience one channel output only it might be correct about this behavior and also the overlay seems correct.
In case you're interested in the output summary:
As long as you keep the discussion about this at their place...
ophub is (ab)using the name Armbian without permission and they do not contribute to the core development process. Rather they trick users into thinking they get support here and therefore (ab)using our resources.
Yes. This is an example of a rk3588 based board of mine:
overlay_prefix=rockchip-rk3588
overlays=panthor-gpu opp-oc-24ghz
The overlay names come from /boot/dtb/*/
find an overlay matching your soc and needs and enable by putting its name to overlays=. Then reboot. Having a serial console to read uboot logs can show if it has been loaded properly or in case it did not why.
Expected. current had a bare minimum of hdmi support before it became recent LTS kernel. Therefore no fixes will hit there until rollover to next LTS.
Needs to be enabled. Either enable panthor overlay (the mainline panthor driver was backported to vendor kernel but is disabled by default) and install more recent mesa packages (depends on userspace). Or install proprietary mali blobs.
Having or building an image with mesa-vpu extension enabled handles that for you. There is no automatic method of installing afterwards yet. https://github.com/armbian/apa/issues/20
The easiest route is to simply flash it to a microsd card and boot from it.
Once booted issue "armbian-install" to move the OS and boot loader to eMMC.
eMMC should be accessible directly if tools like rkdeveltool or whatever that is called is used. Never used that personally, seems tricky to use. Prefer first path.
Not having correct uboot on spi can often lead to such issues.
Also sometimes vendor kernel does not like mainline uboot and vice versa. This is why vendor kernel based images usually are shipped with vendor uboot which is version 2017.09 I think.
Anyway glad you figured it out