playback issues

I usually just playback through the speakers on my laptop. But for some reason, I am getting a message ‘error opening sund device. Try changing the audio host, playback device and project sample rate.’
When the soundcard is plugged in through USB- playback works. It’s only when I unplug that I get this message.
Sample rate is 44100 and it has alays worked until today.
Any suggestions? Thanks

Try rebooting your computer, then when you launch Audacity, in the device toolbar, set “host” to “MME” and select the required devices for recording and playback.