My older PVR PC (with Nvidia 8400GS graphics card) is still happily running LinHES R6 (from 2011) but I recently tried to replace my 18-year-old Sony 1080p TV monitor with a new 4K Sony TV and the HDMI SPDIF audio stopped working.
Specifically, the audio and video worked great if I booted LinHES with the old TV attached and moved the cable to the new TV. But if I booted up with the new TV attached, there was no sound regardless how I configured the audio settings in LinHES and MythTV. This implied that there was some difference in the EDID data between the old and new TV that the old Nvidia graphics driver didn't like.
My kludge to work around this audio issue was to use the "Acquire EDID" option in the "nvidia-settings" app to save the EDID data to a file when the old TV was attached, and then add an option line to the Screen section of my /etc/X11/xorg.conf file to tell the nvidia driver to use that EDID file from the old TV.
Code:
Option "CustomEDID" "DFP:/etc/X11/edid-oldtv.bin"
Note that this assumes that the new TV will be happy with all of the other video mode settings in the old EDID file. A better fix would be to edit the EDID file captured from the new TV and just remove the unwanted audio sections (still using the CustomEDID option to point to a new EDID file). [I will be working on that next.]
Another workaround would be to upgrade to LinHES R8 which seems to work just fine with the new TV.
