If it’s not, then one might have the wrong package installed. If one is using PulseAudio, one needs pulseaudio-alsa. If one is using PipeWire, one needs pipewire-alsa.
Disclaimer: The manjaro-pulse and manjaro-pipwire meta packages are only provided as a convenience. Manual intervention is required. There’s no way around it, unfortunately. If they’re causing too much confusion and problems, they can be dropped.