no sound in MP3 export from Audacity

I made a voice recording in Audacity 2.0.3 (dmg installer), amplified it a bit, and the audio sounded fine. Then I exported it as an MP3 file, and there’s no sound in the MP3 playback. I’ve done this dozens of times and have never had a problem before. Would you have any idea what’s causing this? Thank you.

The current Audacity version is 2.0.5: .

Where are you playing the MP3 where it has no sound?

If you used a USB recording device, unplug it from the computer.

You can check Mac audio settings in the “Sound” system preferences.