That is the same error as here reported on the Pi4
Would be interesting to see if adding one of these options to config-user.txt makes a difference
dtparam=audio=on
dtoverlay=pisound
Also the output of edid-decode /sys/class/drm/card?-HDMI-A-1/edid edid-decode /sys/class/drm/card?-HDMI-A-1/edid
could be of interest.