Since you can upgrade the firmware only under Windows, I've for a suggestion for you: Create Windows 10 installation media, using Microsoft Media Creation Tool:
Download Windows 10 . Install Windows 10, temporary, only for firmware upgrade. During Windows installation, click on "I don't have a product key" when you will be asked to insert one. The installation process will continue till ends. Window will work few weeks without activation, just enough for you to upgrade the firmware. After firmware upgrade, you will return to your Ubuntu. I know that this is long way, but if you want have good audio ... you can do it.
This is exactly what I am trying to avoid doing, I don't really want to wipe everything off my device and rebuild it again so that I can install a firmware patch.
I attempted to work around it by using Windows 10 To Go (A windows live image essentially for the *nix users), but for whatever reason that doesn't want to boot on the skull canyon either so I'm pretty much screwed at this point.
Installing Windows as I've have described in my post #3 is for now the best if not only way to update your firmware. Before installing Windows you shall make an image of your disk and restore it after firmware upgrade. In the net you can find different tutorials how to do such disk image for Linux.
So here's how I installed the firmware updates without destroying any data:
- dd the data on the hdd to a backup drive.
- Use a linux live image to shrink the ext4 partition.
- Put an NTFS partition on the newly reclaimed space.
- Install windows on to that partition.
- Boot into the new windows partition and install the firmware updates.
- Boot back into the live image and install boot-repair and then run it to restore the grub boot loader that windows destroys.
That said though even when using the windows partition, the only audio option available in windows seems to be 2.0. I pretty much just gave up and decided to let the TV do the up-mixing, it's not perfect but I think I'm done fiddling.
I am sorry that you had to go thru that process to get Windows on the system just to update the HDMI 2.0 firmware. This request to have a Linux version has been forwarded up to the product developers but there are no plans for now. I will keep asking.
Thanks for letting us know all the details and even if not perfect I hope that you have a good experience with the product.
I would too appreciate if I have the option to upgrade the HDMI firmware without need to go through all the pains with windows installation on the machine. I would understand if it was an issue with some noname equipment made by some garage company. But your are claiming that you are the industry leader, so prove it, and make the OS independent solution for us.
For good reason, Linux is not a formally-supported environment. Formally supporting and validating Linux - even if only a single release of a single distro - will cost five to ten thousand dollars and this cost would need to incorporated (absorbed) into the cost of all of the units sold. I am sure that those folks using Windows - which represent likely 95% of all NUC purchasers - are not going to be willing to pay a significantly-extra amount for their units just to cover the cost of this Linux validation (that they are never going to use)...