How To Batch Convert M4A Audio Files Into MP3 Audio Files
Here is one way to convert a bunch of m4a audio files into mp3 audio files using the free and open-source Audacity audio editor.
This video walks you through the steps to convert 1 or 100 (I demonstrate with 4) m4a audio files into mp3 audio files. The speed of the conversion is determined by the power of your computer, the number of files being converted, and the overall size of those files.