Theory: HiFiBerry driver has been updated since newer LE versions, so it's not working with your clone anymore.
Solution: Buy an original HiFiBerry soundcard. They are working fine on LE since many years.
Before buying a new soundcard, you can try Raspberry Pi OS with Kodi. If it's also not working there, my theory is confirmed.
I dont know which instructions you are talking about in Raspberry PI OS.
The hardware package has to have some instructions for driver installation. That's what I wanted to see.
It seems to use the HiFiBerry driver, but the soundcard is a HiFiBerry clone, so mysterious things can happen. 
LE's standard configuration schema is a read-only default config, and a user config, which has to be created if needed.
Read here: Samba service- query about default settings and users
I guess you're scared because of this thread: Can't connect to MariaDB server after updating to 11.0.1
You can downgrade back to LE10 any time, so just try LE11, and report.
Boot GParted Live from a thumb drive on your Windows PC, and follow plan A. Be careful.
Will this be the same on Raspberry Pi5 ??
Yes. Anything else would be a step backwards.
A license fee has to be payed for Dolby Vision, so Kodi will never support it.
Kuman SC07C Raspberry Pi HiFi Digi+ with spdif.(Soundcard)
That package contains the PiFi Digi+ soundcard, not the original HiFiBerry Digi+. So the driver at config.txt doesn't work for you.
the sudo command can be typed in raspbian session in the pi console I guess. I didnt try it so far because I dont know which commands to type.
LE doesn't support sudo, because you're already super user after login. I assume you have instructions, how to install the driver on Raspberry Pi OS (former Raspbian). Please share a link of those instructions. Maybe we can help to install that driver on LE.
I'm connecting to HDMI2.
What about HDMI-1?
Sep 10 11:57:56.355406 LillyELEC xorg-launch[1067]: ================ WARNING WARNING WARNING WARNING ================
Sep 10 11:57:56.355406 LillyELEC xorg-launch[1067]: This server has a video driver ABI version of 25.2 that this
Sep 10 11:57:56.355406 LillyELEC xorg-launch[1067]: driver does not officially support. Please check
Sep 10 11:57:56.355406 LillyELEC xorg-launch[1067]: http://www.nvidia.com/ for driver updates or downgrade to an X
Sep 10 11:57:56.355406 LillyELEC xorg-launch[1067]: server with a supported driver ABI.
Sep 10 11:57:56.355406 LillyELEC xorg-launch[1067]: =================================================================I guess you have to downgrade LE to get the right NVIDIA driver: Click!
No support for outdated LE versions, sorry.
Tell us what you want to install, and we are able to give more useful instructions.
No, dedicated add-ons are the only type of package management. If you have to have such packages, drop LE, and install Ubuntu with Kodi on auto-start.
It's plug-and-play after pairing.
I wasn't sure how far the boot process went, thanks. So we are still at kernel level. Does it boot with Ubuntu?
So, last night, to test with, I installed Ubuntu on it just to see if it's a driver issue before I gave up. Funny enough same issue. I installed alsa-tools, and alsa-tools-gui, from a post I found somewhere, selected "unconnected pins" and have overridden them with Displayport/HDMI, and it worked.
...Worst case, if we cannot get LibreElec to work, not the end of the world, I'll just Ubuntu+Kodi it haha!
Can you share that Ubuntu link? I have no clue what "unconnected pins" means here.
And how do you edit cmdline.txt on the FAT32 partition from Libreelec?
Same way as config.txt.
