Created attachment 561938 [details] emerge --info (xz-compressed) media-video/mpv used to work just fine (audio) with the pulseaudio use flag. But after the recent update to media-sound/pulseaudio-12.2 I don't have any sound anymore. Rebuilding media-video/mpv without the pulseaudio use flag does work just fine.
Can you still reproduce this problem? Do other applications work with pulseaudio? You may also try reading the following wiki articles: - https://wiki.gentoo.org/wiki/PulseAudio#Troubleshooting - https://wiki.archlinux.org/index.php/PulseAudio/Troubleshooting
This bag description is too generic, please gather more information so we can determine what's going on.