I've installed ubuntu several times, using different SSDs and install options. It will boot to the installer fine, I install fine, it reboots fine. But after a second reboot (or maybe three, don't recall exactly), when I reboot it goes to a generic udoo splash screen and hangs. In order to get it to boot again, I have to take it apart, plug in the install USB drive to boot it, then shut down and reinstall the SSDs. Then it will boot normally, but only once. If I shut down or reboot again, I have to restart this process. I'm using ubuntu 18.04.4. I did install the 19 version you have posted, but that is out of support now and many of the tools I need won't install for some reason. Is this a known issue and is there a fix coming? I've been dealing with this for a couple of months now, hoping a bios update would be forthcoming.