I'm trying to export a selected audio file from the timeline by choosing "produce selection as" and then choosing "custom production settings." From what I understand, there should be an MP3 option, but there is not (only MP4). Is there another way of doing this?
Camtasia doesn't support mp3 anymore It's .wav or .m4a
In the top menu, go to "Share" then "Export Audio Only" You can save as .wav or .m4a
Another way for just a .m4a file is Do a "Custom Production" and select "M4A audio only"
If you really need it as mp3 you will have to convert it. Audacity (Free and open source) does a really good job of doing that.
Another way is to extract the audio from a mp4 video using Audacity. Just drag and drop your mp4 video on to Audacity and it will put just the audio on its timeline and you can save it as a mp3. I personally use this method all the time. Faster and I can then edit or modify the audio if needed before saving out as a mp3