$ systemctl --user status pipewire pipewire-pulse wireplumber
# this should complete immediately and display info such as
# Active: active (running)
# Active: inactive (dead)

$ systemctl --user restart pipewire pipewire-pulse wireplumber
# the above restart may take several minutes to complete;
# do not do this if you are about to join an online meeting,
# your audio devices may not be available in time

$ systemctl --user restart pipewire.service wireplumber.service
# the above restart may take several minutes to complete