sudo pacman -S pulseaudio-bluetooth
pulseaudio -k
# reinstall bluetooth
sudo apt --purge --reinstall install bluetooth bluez blueman pulseaudio pulseaudio-module-bluetooth
# at
sudo nano /etc/pulse/default.pa
# add load-module module-bluez5-discover
# then
sudo killall pulseaudio
pulseaudio --start
sudo systemctl restart bluetooth.service