M4A (short for MPEG-4 Part 14) is an audio file which uses MPEG-4 multimedia container format to store data. MPEG-4 file extension is officially known as MP4, and such files can store both audio and video data. However, M4A files can only store audio data. The format was developed by Apple in 2004 and is based on QuickTime format.
Two types of compresssion
Most audio data in M4A is encoded using Advanced Audio Coding (AAC) codec. Some M4A files, however, utilize Apple Lossless Audio (ALAC) lossless compression algorithm. Compression allow files to be smaller, and thus can more easily be shared over the internet.
M4A and MP3 – a comparison
M4A format is basically an enhanced MP3 format, although it was initially designed not only as a audio container, but as a part of MPEG-1 or MPEG-2 layer 3 standard. M4A and MP3 share many similarities, for example, both formats use compression, but M4A technology offers better audio quality when encoded at the same bitrate. M4A files are also smaller than MP3 and offer two types of compression – lossy and lossless. All the advantages M4A format offers stem form better compression algorithms, smaller sample block size, and larger stationary signal block.
Uses of M4A format
M4A format is commonly used for distribution of audio tracks on iTunes Store, but only for those files that are not copyrighted. DRM-protected files used the M4P format.
Programs which support M4A file extension
The list that follows enumerates programs compatible with M4A files, divided into 4 categories based on operating system on which they are available. M4A files can be encountered on all system platforms, including mobile, yet there is no guarantee each will properly support such files.
There can be multiple causes why you have problems with opening M4A files on given system. Fortunately, most common problems with M4A files can be solved without in-depth IT knowledge, and most importantly, in a matter of minutes. The following is a list of guidelines that will help you identify and solve file-related problems.
Step 1. Download and install iTunes
The main and most frequent cause precluding users form opening M4A files is that no program that can handle M4A files is installed on user’s system. The most obvious solution is to download and install iTunes or one to the listed programs: Winamp, QuickTime Player, Windows Media Player. Above you will find a complete listing of programs that support M4A files, classified according to system platforms for which they are available. The safest method of downloading iTunes installed is by going to developer’s website (Apple, Inc.) and downloading the software using provided links.
Step 2. Verify the you have the latest version of iTunes
If the problems with opening M4A files still occur even after installing iTunes, it is possible that you have an outdated version of the software. Check the developer’s website whether a newer version of iTunes is available. Sometimes software developers introduce new formats in place of that already supports along with newer versions of their applications. The reason that iTunes cannot handle files with M4A may be that the software is outdated. All of the file formats that were handled just fine by the previous versions of given program should be also possible to open using iTunes.
Step 3. Set the default application to open M4A files to iTunes
If you have the latest version of iTunes installed and the problem persists, select it as the default program to be used to manage M4A on your device. The process of associating file formats with default application may differ in details depending on platform, but the basic procedure is very similar.
Selecting the first-choice application in Windows
Clicking the M4A with right mouse button will bring a menu from which you should select the Open with option
Select Choose another app → More apps
To finalize the process, select Look for another app on this PC entry and using the file explorer select the iTunes installation folder. Confirm by checking Always use this app to open M4A files box and clicking OK button.
Selecting the first-choice application in Mac OS
Right-click the M4A file and select Information
Proceed to the Open with section. If its closed, click the title to access available options
Select the appropriate software and save your settings by clicking Change all
Finally, a This change will be applied to all files with M4A extension message should pop-up. Click Continue button in order to confirm your choice.
Step 4. Check the M4A for errors
Should the problem still occur after following steps 1-3, check if the M4A file is valid. Being unable to access the file can be related to various issues.
1. Verify that the M4A in question is not infected with a computer virus
If the file is infected, the malware that resides in the M4A file hinders attempts to open it. Scan the M4A file as well as your computer for malware or viruses. If the scanner detected that the M4A file is unsafe, proceed as instructed by the antivirus program to neutralize the threat.
2. Check whether the file is corrupted or damaged
If the M4A file was sent to you by someone else, ask this person to resend the file to you. It is possible that the file has not been properly copied to a data storage and is incomplete and therefore cannot be opened. It could happen the the download process of file with M4A extension was interrupted and the file data is defective. Download the file again from the same source.
3. Ensure that you have appropriate access rights
Some files require elevated access rights to open them. Log out of your current account and log in to an account with sufficient access privileges. Then open the MPEG-4 Audio Format file.
4. Verify that your device fulfills the requirements to be able to open iTunes
If the system is under havy load, it may not be able to handle the program that you use to open files with M4A extension. In this case close the other applications.
5. Check if you have the latest updates to the operating system and drivers
Latest versions of programs and drivers may help you solve problems with MPEG-4 Audio Format files and ensure security of your device and operating system. Outdated drivers or software may have caused the inability to use a peripheral device needed to handle M4A files.
Conversion of a M4A file
File Conversions from M4A extension to a different format
If you have additional information about the M4A file, we will be grateful if you share it with our users. To do this, use the form here and send us your information on M4A file.
Windows 
MAC OS 
Linux 
Android 
The main and most frequent cause precluding users form opening M4A files is that no program that can handle M4A files is installed on user’s system. The most obvious solution is to download and install iTunes or one to the listed programs: Winamp, QuickTime Player, Windows Media Player. Above you will find a complete listing of programs that support M4A files, classified according to system platforms for which they are available. The safest method of downloading iTunes installed is by going to developer’s website (Apple, Inc.) and downloading the software using provided links. 
If the problems with opening M4A files still occur even after installing iTunes, it is possible that you have an outdated version of the software. Check the developer’s website whether a newer version of iTunes is available. Sometimes software developers introduce new formats in place of that already supports along with newer versions of their applications. The reason that iTunes cannot handle files with M4A may be that the software is outdated. All of the file formats that were handled just fine by the previous versions of given program should be also possible to open using iTunes.
