@Octavio Cuatrochio@Thur_Wander Maybe it has secure boot enabled.

Hi, I am here in 2026 with the Amrbian 26.2.1, I've tried the proposed fix from @c0rnelius but it's not working on my OS version. If anyone has any updated solution that'd be amazing. Thank you

I have this exact same model and the device appears to be heavily locked down... Did this method worK? i'm trying to get a linux ARM distribution running but i can't flash a custom ROM

The most current download images for Helios64 are now all provided with linux 6.18.xx. I downloaded a minimal image and checked the dtb: it would not appear to contain the opp-microvolt patch that made Helios64 finally stable. So for the ones who have stability issues again on Helios64, I attached the patched dtb compiled for linux 6.18.xx using the exact same opp-microvolt values as in the previous dtb versions I compiled for linux 6.6 and 6.12. The current linux deb files can be downloaded from beta.armbian.com, the linux 6.18.18 deb files I used can be downloaded from here (to be installed with 'dpkg -i linux*'). In order to install the dtb, simply unzip it, copy it into the proper location, update initramfs and reboot: # install the dtb with the opp-microvolt patch: unzip rk3399-kobol-helios64.dtb-6.18.18-opp.zip cp rk3399-kobol-helios64.dtb-6.18.18-opp /boot/dtb/rockchip/rk3399-kobol-helios64.dtb update-initramfs -u reboot rk3399-kobol-helios64.dtb-6.18.18-opp.zip

Another attempt, again check https://testing.armbian.de/r4s/?C=M&O=D for most recent debs. This time adding an artificial bus scan delay into the r4s dts. Another poke in the dark but perhaps...