Distros *should* be doing this by default these days, but try this in ~/.asoundrc or /etc/asound.conf: pcm.!default { type pulse hint.description "Default Pulseaudio Device" } ctl.!default { type pulse hint.description "Default Pulseaudio Device" }
You want to run `pavucontrol` to see what's going on. Any audio playing app that *doesn't* show up there is not using PulseAudio and most likely blocking the audio device (this could be YT/Spotify in your case, if you don't have the above config).
