core/pulseaudio/pulseaudio.install

post_upgrade() {
  echo -e '\e[31;46m WARNING \e[0m'
  echo 'If you have per-user copies of configuration files in ~/.pulse/,'
  echo 'make sure you keep them in sync with changes to the packaged files in /etc/pulse/.'
  echo 'Otherwise, PulseAudio may refuse to start due to configuration errors.'
  echo 'Deleting ~/.pulse/ is another option to avoid these configuration errors.'
}