Dummy Audio Device

[royleith]

I recently updated from 18.10 because it insisted on asking for my WiFi password up to four times without connecting. 19.04 is fine with WiFi.

Audio is a problem. On the first boot after installation and for several more sessions, audio was fine. Then audio programs refused to play. The System Tray icon and the Audio and Video settings showed only a 'Dummy Device'. I tried to pair up Bluetooth as a wprk-around, but it would not appear in audio settings.

After a couple of reboots, the internal audio device (Intel HD) appeared and audio via Line Out was back. I tried to pair Bluetooth, again and this time Bluetooth was paired successfully and I was able to switch the sound to Bluetooth. The Bluetooth player appeared against the loudspeaker icon. However, audio programs still play via Line Out rather than Bluetooth. The Bluetooth device (a multi-input audio switcher) reports 'No Signal'. In Audio and Video Settings, the internal card works when the Test button is clicked, but the Bluetooth device does not produce any sound.

I checked that alsa-utils was installed and reinstalled them, just in case. None of alsamixer, amixer or asound would run in Konsole. The alsamixer library appears in /usr/bin. I was hoping to run asound to check the sound devices, but Konsole says 'No file or directory'..

The situation, now, is that I may have to reboot a couple of times before audio is restored. Ubuntu Studio (18.10) audio is fine on the same computer.

I noticed that someone else started with USB connected audio and found that he couldn't drop back to the internal audio card. That was resolved after a reboot, but I suspect that he is back on the USB audio device by now and may not have noticed that the internal audio device has gone missing, again.

Has anyone else noticed this happening and does anyone have a cure?

[royleith]

The 'Dummy device' turns up most times, now, but Bluetooth is connecting properly every time.

Since the Bluetooth receiver is connected to a pair of studio monitors, this is quite a good arrangement. I would still like to get my internal sound card up and running, again.

[royleith]

I checked that the audio chips were detected and a suitable module was in use:

lspci -nnk | grep -A2 Audio
00:1f.3 Audio device [0403]: Intel Corporation 200 Series PCH HD Audio [8086:a2f0]
Subsystem: ASUSTeK Computer Inc. 200 Series PCH HD Audio [1043:8723]
Kernel driver in use: snd_hda_intel
Kernel modules: snd_hda_intel

It was suggested that, for the Intel chip, you need to add options snd-hda-intel model=generic at the end of the /etc/modprobe.d/alsa-base.conf file. Then reboot.

This did not work for me.

Then, If you continue to get no sound output and still only see the Dummy Output in System Settings, you can try to set the model to auto instead of generic.

This did not work for me.

Then,

sudo alsa force-reload

This did not work for me.

Finally, uninstall and reinstall alsa-base pulseaudio. The uninstall (suggested for Ubuntu) removed Plasma components and made the system unusable.

A reinstall of Kubuntu seems to have restored audio.