I had working audio on the Nano from the HDMI port with the nVidia official release of Ubuntu 18.04, of the dev kit SD. I upgraded to Ubuntu 18.10 to check compatibility with the Nano. Now HDMI audio no longer works. I have it switched in settings from Analog to HDMI.
I realize 18.10 is not the supported official build for the Nano, but I would like to try to get the HDMI sound working again on 18.10 if possible. I would imagine the upgrade either over-wrote settings files, or possibly the upgrade removed select nVidia driver files as not needed.
Could someone offer insight/instruction/thoughts on how the HDMI audio was set up in the nVidia Ubuntu 18.04 version, so I could attempt to fix this?
I found the problem, well, by accident. I have two monitors, both are connected with HDMI cable. When I change the monitor, the option “HDMI/DisplayPort” showed up.
It turns out that the other monitor failed to show the HDMI sound output was connected to HDMI cable through a DVI adapter.
In other words, you must connect your monitor directly through a HDMI cable to see the sound option in the system settings.