Ok, tentei mudar para desabilitar o fone de ouvido e matá-lo completamente. As seleções teriam apenas (desconectado) depois deles, então nenhum áudio seria produzido:
Enable=Source,Sink,Gateway,Control,Media
Disable=Socket,Headset
$ sudo service bluetooth restart
bluetooth stop/waiting
bluetooth start/running, process 8552
$ sudo alsa force-reload
Unloading ALSA sound driver modules: snd-seq-midi snd-seq-midi-event snd-seq snd-rawmidi snd-seq-device snd-hda-codec-hdmi snd-hda-codec-realtek snd-hda-codec-generic snd-hda-intel snd-hda-controller snd-hda-codec snd-hwdep snd-pcm snd-timer (failed: modules still loaded: snd-hda-codec-hdmi snd-hda-codec-realtek snd-hda-codec-generic snd-hda-intel snd-hda-controller snd-hda-codec snd-hwdep snd-pcm snd-timer).
Loading ALSA sound driver modules: snd-seq-midi snd-seq-midi-event snd-seq snd-rawmidi snd-seq-device snd-hda-codec-hdmi snd-hda-codec-realtek snd-hda-codec-generic snd-hda-intel snd-hda-controller snd-hda-codec snd-hwdep snd-pcm snd-timer.
$ pulseaudio -k
Então eu coloquei de volta e começou a funcionar novamente:
Enable=Source,Sink,Gateway,Control,Media,Headset
Disable=Socket
$ sudo service bluetooth restart
bluetooth stop/waiting
bluetooth start/running, process 15071
Como isso faz sentido eu não sei. Às vezes o linux é o pior!