How to resolve Pulseaudio not attaching a mixer due to missing libraries?

"Here's a straight answer: PulseAudio is a sound server; ALSA is a kernel sound subsystem. They do different things -- ALSA provides chipset drivers for your soundcard or onboard sound chip; PulseAudio routes sound between programs, sound chips, and even systems.

PulseAudio is a sound server for POSIX systems. A sound server is basically a proxy for your sound applications. It allows you to do advanced operations on your sound data as it passes between your application and your hardware. Things like transferring the audio to a different machine, changing the sample format or channel count and mixing several sounds into one are easily achieved using a sound server.

To use PulseAudio, you need a sound driver somewhere. This can be ALSA or OSS; these provide the kernel sound drivers to output sound signals from the computer.

Follow the steps at the First Steps page to bring up a PulseAudio commandline; you can use the CLI to test whether things are running right.

# get a pulseaudio commandline
$ pulseaudio -nC

Welcome to PulseAudio! Use ""help"" for usage information.

# run this to see what sinks are configured
>>> list-sinks

Also check your /etc/pulse/daemon.conf and /etc/pulse/default.pa config files (they may be installed to /usr/local/etc/pulse if you compiled & installed PA yourself)."

"This files is a part of alsa-plugins-pulseaudio. System had alsa-plugins-pulseaudio-1.1.5-1.fc27.i686 installed but x86_64 was missing. So I did:

sudo dnf install alsa-plugins-pulseaudio-1.1.5-1.fc27.x86_64

Hope that was helpful."