can not switch between sound devices

[Ralf Mardorf]

On Sun, 15 Nov 2020 08:55:05 +0100, Gary J. Kirkpatrick wrote:
>sudo apt-get install --reinstall alsa-base pulseaudio
>
>sudo alsa force-reload
>
>Anything else I can do to get the Ubuntu desktop sound switching to
>work correctly?

Hi,

I'm not a follower of the reinstall and/or reboot approach. However, if
you want to follow this approach, then for testing purpose do the
complete thing. First try to run

  sudo apt purge alsa-base pulseaudio

It much likely will not work, due to dependency conflicts. There much
likely is an option mentioned by the apt-get and/or dpkg man page, how
to allow the removal of packages, by breaking dependencies.

Once alsa-base and pulseaudio and their configuration files are purged
run

  sudo apt install alsa-base pulseaudio

after that add a new user, since user specific configurations were not
purged.

Then do not reload alsa and do not stop and start pulseaudio. Restart
the computer!

1. killall pulseaudio

is unlikely good for anything at all. I don't have this sound server
installed, but I often read that there are special commend to really
stop and start pulseaudio.

2. While the alsa reload might happen, it's better to restart the
machine. At least for real time audio there are some known issues, that
are hard to get rid of without a restart. It might not affect your
use case, but you never know.

3. At least for testing purpose log in as your brand new user.

Regards,
Ralf