[arch-general] pavucontrol can't connect to Pulseaudio

[Arno Gaboury]

Dear list,

pulseaudio is started with my X session via 
/etc/X11/xinit/xinitrc.d/pulseaudio.

[gabx at magnolia:~]$ ps aux | grep pulse
gabx       687  0.0  0.0 501896  6652 ?        S<l  15:12   0:00
/usr/bin/pulseaudio --start

My issue is with pavucontrol, the GTK volume control tool.
When I start pavucontrol, the volume control windows opens but hangs
with this message:
Establishing connection to Pulse Audio. Please wait...
and never open.
I see in the log file : [pulseaudio]pid.c : Daemon already running.

Why can't pavucontrol access to pulse audio??

This issue didn't appeared when I booted with sysvinit, but it came when
using systemd. 

TY for help