• Install paprefs
• In paprefs activate:

Network Server-> Enable network access to local sound devices
Network Server-> Allow other machines on the LAN to discover local sound devices
Network Server-> Don't require authentication

• Run the following commands on the server console:

pactl load-module module-zeroconf-publish
pactl load-module module-native-protocol-tcp auth-anonymous=1

• On the client paprefs:

Network Access-> Make discoverable PulseAudio sound devices available locally