Hi
I’m new to the forum but have been using Fedora since way back with FC4. I used to mostly access via VNC but with the Windows 10 debacle, I decided it was time to actually sit at my KDE desktop.
I’ve spent some time struggling to get audio working and eventually stumbled across something I don’t understand, maybe my observations will be useful to others.
My setup has two iiyama XUB27292QSU displays. One is about 3 years old, the other the one on which the audio doesn’t appear to work is new.
Both have the same model number but they are a little different, the older has HDMI/DVI interfaces the newer has HDMI/Display Port.
Fortunately I have two FC43 machines with identical motherboards and GT710 graphics cards, one is an upgrade and HDMI audio works fine on this.
The other had been upgraded 6 or 7 times so I thought it was due a clean install. It is on this machine that the audio did not work out of the box.
Having the second machine gave me great confidence that the GT710 and the nouveau driver would produce audio and avoided time looking for other driver options.
I quickly got to the point where output in the boot log as the audio driver is installed is identical between the two machines.
Pipewire is new to me so I did most of my testing with “speaker-test” and “aplay” as this cuts pipewire issues out of the equation.
aplay -L produced the same output on both machines. Probably the most important lines in the output are :-
Default ALSA Output (currently PipeWire Media Server)
hdmi:CARD=NVidia,DEV=0
HDA NVidia, PL2792Q
HDMI Audio Output
So the HDMI audio interface in the monitor is seen and the monitor is correctly identified as a ProLite 2792Q.
But
speaker-test -c 2 -D hdmi:CARD=NVidia,DEV=0
fails to produce any audio on the freshly installed machine.
To test the audio connectivity I pulled the HDMI cable out of the GT710 card and plugged it into a laptop. Sound was generated by the display, so I assumed the fault lay with the Fedora install/config.
After a couple of days getting nowhere I swapped the screens on my two monitor setup.
To my amazement after swapping the screens the audio worked.
What can I conclude
Even if aplay -L reports the audio device if the connection is over HDMI this doesn’t guarantee audio will be produced.
There is some subtle difference between the two XUB27292QSU monitors.