I’ve been using Audacity for some time, and have recently had problems with the types of files the program will accept. For a while, I had to save the file as .aiff before converting it to mp3, because I (allegedly) didn’t have the Lame program to deal with mp3s. (I did try to download the program, honest.) Now it’s claiming that an m4a file is an “Advanced Audio Coding File” that cannot be accepted by Audacity; it needs to be “converted to a supported audio format, such as WAV or AIFF.”
When I click on the “?” help button, it says: “Audacity can import unprotected files in many other formats (such as m4a and wma) if you download and install the optional FFmpeg library to your computer." I tried that as well. No dice.
You’ll have to get better at downloading and installing software. Lame for creating new MP3 files and FFMpeg for both opening and creating files with newer compression formats.
Scroll down and follow the processes for the software. We are going to ask you exactly where you got stuck. “It didn’t install” isn’t descriptive enough.
It’s not optional. Audacity will not handle many of the newer formats without extra software packages.
Not correct, assuming you are using the current Audacity 2.1.0 from Audacity ® | Download for Mac OS (please see the pink panel at the top of the page for the information we needed from you).
In that 2.1.0 version, M4A (AAC) audio files should import using the built-in QuickTime codecs, without installing FFmpeg, as long as you set the file type selector in the open/import dialogues to “All files” or “All supported files”, and as long as you haven’t added special import rules in the “Extended Import” Preferences.