In theory it should be done by the default-device-restore module, but it might not work for HDMI as it's a dynamic setup. Please check whether the setup described below works: https://www.freedesktop.org/wiki/Software/PulseAudio/Documentation/User/DefaultDevice/ Also, the troubleshooting page of Arch linux might help: https://wiki.archlinux.org/index.php/PulseAudio/Troubleshooting