What
Kill and restart the macOS coreaudiod daemon when system audio stops working.
Why
After sleep/wake cycles or OS updates, the audio daemon can hang while apps still think output is available. macOS respawns coreaudiod automatically once you kill the stuck process — no reboot needed.
How
sudo kill $(ps -ax | grep 'coreaudiod' | grep 'sbin' | awk '{print $1}')
Audio will restart automatically.