Comment 28 for bug 1828136

I rebooted and went into the "Ubuntu" desktop and looked at the sound settings. It shows an output tab and said "dummy". I clicked and was able to switch it to the nvidia card. I think maybe the nvidia card was off, which it should be since there's no output device connected.

I went back into my regular environment and observed that the nvidia output was available but not the built-in sound. I ran aplay test.wav and could see in pavucontrol that sound output was going to the nvidia output. (It shows a real-time output level bar.)

I ran alsa force-reload. When I do this the message "Terminating processes: <pid>" appears and instantly at that point, the built in sound appears in pavucontrol on the configuration tab. For some reason though, in this case, even after I selected it, I still got no sound. I rebooted again, went straight into my normal environment, confirmed that only the nvidia card was available, ran 'alsa force-reload', the built-in sound appears instantly as described above, then there is a many second delay while alsa loads and messages about loading of sound driver modules appears. And then I can play sound, e.g. with aplay.