Pulseaudio not working, daemon already running and no permission for home folder

I'm using Ubuntu 16.04.4 LTS, and the sound "suddenly" stopped working. I have been playing around with the issue for some time, so it's possible that I added another layer of problems on top of the original one. The situation at the moment is the following:

pulseaudio produces

E: [pulseaudio] pid.c: Daemon already running. E: [pulseaudio] main.c: pa_pid_file_create() failed.

Running it as sudo pulseaudio:

E: [pulseaudio] core-util.c: Home directory not accessible: Permission denied

Then, I tried the solution proposed by this question to fix the accessibility problem of the home directory:

sudo chown -R giovanni:giovanni /home/giovanni

but with no apparent effect. Running pavucontrol works fine.

The output of pulseaudio -vvvvv is as following:

I: [pulseaudio] main.c: setrlimit(RLIMIT_NICE, (31, 31)) failed: Operation not permitted
I: [pulseaudio] main.c: setrlimit(RLIMIT_RTPRIO, (9, 9)) failed: Operation not permitted
D: [pulseaudio] core-rtclock.c: Timer slack is set to 50 us.
D: [pulseaudio] core-util.c: RealtimeKit worked.
I: [pulseaudio] core-util.c: Successfully gained nice level -11.
I: [pulseaudio] main.c: This is PulseAudio 8.0
D: [pulseaudio] main.c: Compilation host: x86_64-pc-linux-gnu
D: [pulseaudio] main.c: Compilation CFLAGS: -g -O2 -fstack-protector-strong -Wformat -Werror=format-security -Wall -W -Wextra -pipe -Wno-long-long -Wno-overlength-strings -Wunsafe-loop-optimizations -Wundef -Wformat=2 -Wlogical-op -Wsign-compare -Wformat-security -Wmissing-include-dirs -Wformat-nonliteral -Wpointer-arith -Winit-self -Wdeclaration-after-statement -Wfloat-equal -Wmissing-prototypes -Wredundant-decls -Wmissing-declarations -Wmissing-noreturn -Wshadow -Wendif-labels -Wcast-align -Wstrict-aliasing -Wwrite-strings -Wno-unused-parameter -ffast-math -fno-common -fdiagnostics-show-option -fdiagnostics-color=auto
D: [pulseaudio] main.c: Running on host: Linux x86_64 4.4.0-130-generic #156-Ubuntu SMP Thu Jun 14 08:53:28 UTC 2018
D: [pulseaudio] main.c: Found 4 CPUs.
I: [pulseaudio] main.c: Page size is 4096 bytes
D: [pulseaudio] main.c: Compiled with Valgrind support: no
D: [pulseaudio] main.c: Running in valgrind mode: no
D: [pulseaudio] main.c: Running in VM: no
D: [pulseaudio] main.c: Optimized build: yes
D: [pulseaudio] main.c: FASTPATH defined, only fast path asserts disabled.
I: [pulseaudio] main.c: Machine ID is 5557250d9a584b4babf69038dc518427.
I: [pulseaudio] main.c: Session ID is c2.
I: [pulseaudio] main.c: Using runtime directory /run/user/1000/pulse.
I: [pulseaudio] main.c: Using state directory /home/giovanni/.config/pulse.
I: [pulseaudio] main.c: Using modules directory /usr/lib/pulse-8.0/modules.
I: [pulseaudio] main.c: Running in system mode: no
E: [pulseaudio] pid.c: Daemon already running.
E: [pulseaudio] main.c: pa_pid_file_create() failed.

I tried to remove and reinstall pulseaudio (several times) but with no success. Also, I verified that there's no pulseaudio file in:

~/.config/autostart/

There are no files in:

/etc/X11/xinit/xinitrc.d/pulseaudio /etc/xdg/autostart/pulseaudio-kde.desktop

There is a file in:

/etc/xdg/autostart/pulseaudio.desktop

I would be grateful for any suggestions on what to check or how to fix this issue. Thanks!

I had the same problem, none of the top Google results helped, and I finally found a solution that worked: make sure your user is in the audio group.

I added mine with the following command:

sudo addgroup $USER audio

I had similar issues:

1. sound suddenly stopped
2. not able to change output and input devices
3. not recognized newly added sound adaptor
4. none working microphone
5. none working headphone

and found out that for some reasons multiple pulseaudio servers were running by executing ps x | grep pulseaudio. The following steps solved the problem:

1. Kill all the instances with killall pulseaudio.
2. Start the daemone again with pulseaudio.

After that it worked again.