GMKtec NucBox G10 Resolution Change Issue

    Hi.

    A newbie here although a very long time happy user (but not very techie).

    I have a new GMKtec NucBox G10 (AMD Ryzen 5 3500U) on which I've installed Libreelec 12.2.0 (seemed the most stable at the time but......!). Outputting to an LG TV.

    I have an issue trying to reduce the display resolution from 3840x2160p to 1920x1080p. I'm trying to do this because playback is suffering (e.g. audio only) at the higher resolution. But if I do this and then reboot the Libreelec splash screen appears, freezes, and then a small window with Libreelec in it appears in the top left of the screen.

    Hours of AI (not) assisted (not) help has found no resolution. The best I can get SSH to do is reboot without the error but then the display resolution changes back to 3840x2160p.

    Am I correct to be trying to reduce the resolution to improve playback performance? If so, how can I do it? Would a more up to date Libreelec version help (there was some issue doing this which I've forgotten given the day I've had!)? Is this an issue with this hardware (I've always used Intel before)?

    I tried a forum search but it's hard to come up with a good search term.

    Cheers

    If the current HDMI cables and/or internal firmware (most NUC like devices use an internal DP to HDMI adapter and this has some firmware) have issues with 4K60 but the Kodi GUI (desktop) defaults to 4K60 and "adjust refresh" is not used and/or 1080p modes are not whitelisted, Kodi will upscale everything to 4K60 to compound the problem. It's also possible to have bandwidth issues with uncertified HDMI cables. Have a read of https://wiki.libreelec.tv/configuration/4k-hdr for explanations of recommended config.

    To force 1080p desktop, run tail /sys/class/drm/*/status to understand what connector type/number is in active use. Assuming HDMI-A-1, then add video=HDMI-A-1:1920x1080M@60D to kernel boot params; which will be either the syslinux.cfg file in the root folder of the USB (legacy boot) or EFI/BOOT/grub.cfg on the USB (EFI boot). If the active connector is not HDMI-A-1 adjust the video= command accordingly. This forces the initial kernel DRM state to 1080p@60 and not 4K where it probably defaults to 4K60.

    NB: Some users solve 4K60 issues by using an external DP to HDMI adaptor instead of the HDMI ports on the box. This is not always a guarantee of success as most adaptors are cheap and can also have rubbish firmware; but unlike the internal one soldered to the motherboard, you can order a bunch from Amazon and experiment until you find one that plays nice.