Hey all,
If the sound issues just started happening after 9.2.7 there could be something going on here specific to Mac.
If you haven’t already, see if resetting the in-game options through the Battle.net app gets the sound restored.
After loading up the game again, go into the System → Sound settings and for Game Sound Output try toggling it from “System Default” to “Nosound Driver” to see if sound starts playing. If sound is heard, try swapping back to “System Default” again to see if sound still plays after restarting WoW.
Please let us know the specific model of Mac that you’re using and the macOS version as well so we can collect that info. We’d like to be able to determine if this is a widespread issue with using external speakers (headphone / 3.5mm jack) or limited to specific Mac models or OS versions.
Thanks!