I’ve got FaceTime setup to receive/make calls through my iPhone using my Mac Mini, and normally I’m really happy with it.
However, today it stopped playing back the audio from calls received or made. I tried with the force quit, but that made no difference. I really didnt want to have to reboot my Mac (though I’m pretty sure that would have fixed it), so digging into the App I discovered you can select the audio output from the Video menu (which is why I probably never looked before).
Anyway, selecting a different audio source, placing a call, and then reselecting the original source made all the difference and now I’ve got it working again! Huzzah!