Just did a fresh install of the above on a Rock64 (RK3328) and no sound via HDMI. Went to System>Settings>Audio and tried all the HDMI options but nothing.
Plugged in a USB DAC and no problem with sound output. Is there any configuration file I can edit on LE using the Rock64 to resolve this.
I also have LE 10.0.03 installed on the RockPro64 and no problem with HDMI sound output.