i could solve it as follows:
1- add a new user to the system and to group audio
adduser pi
usermod -a -G audio pi
2- before running pulseaudio i ran
eval "export $(dbus-launch --sh-syntax)"
3- DBUS_SESSION_BUS_ADDRESS=${DBUS_SESSION_BUS_ADDRESS}
4- su -c 'pulseaudio --start' - pi
sudo reboot
-> if it does not connect automatically, do pactl list follwed by bluetoothctl and connect to the speaker.
hcitool con
-> connection xx:xx:xx:xx:xx:xx
pactl list cards short
i get the output
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