Towards the end of 2016 when all of us were busy planning the new year I met with an unexpected digital problem with a recorded media file. Here goes the insight of the issue: -

I recorded an M4A video file using my iPad Mini 2015 edition. The M4A video contained the mouse-flow of a program and my voice with a total size calculating to 75 MB. But towards the end of the video, the program collapsed but managed to save the video file. Once all got fixed, I saw my video not running properly. There existed sound distortion and black screen after it ran about 7 minutes. I fast forwarded the video and after 30 minutes mark the sound came back with visuals. So, overall 23 minutes of the audio-video went berserk.

Resource put to action

Hex Editor

A friend of mine who is a software developer used the hex editor software to look into its hexadecimal values. He told me that this could help diagnose the header file and might possible fix the issue. However, he warned me that it might not work as expected, so we created another copy of the video and used it as a sample for changing the hexadecimal values.

After trying to change (edit) the codes we saved the video but unfortunately, we couldn’t repair the header corruption. I appreciated my friend’s time and effort but 
quickly looked for repairing my corrupt M4A video online.

M4A Repair Online

Got to know about MP4Repair.Org and felt no harm in uploading my video for a repair. So, I used the button ‘Pick a damaged file’ and uploaded the m4a video. Straight away, it came up with 25 minutes of the sound file corresponding to repair 90% of the video data (& audio). Sadly, the MP4 Repair website wanted me to shed $90 to save the fixed m4a video to my desktop.

Like, I know this M4A video for important to me though it was a small video. The text I used in the video, i.e., my voice had come after a good amount of practice sessions, and I had no energy to re-do the video again. But also, I was not prepared to spend USD 90. Though, I appreciated the work done by mp4repair.org.

Software Help to Fix M4A

Like I came across the online M4A repair platform this time I looked for an M4A video repair software which I can download on my Windows desktop. After spending some time on the web, I downloaded Stellar Phoenix Video Repair application. Its source download page said it supported the video file repairing of MOV, MP4, M4A and M4V. The website clearly stated that the evaluation of the application is free but saving corrected video will cost $69. Like, mp4repair online tool the video repair desktop software was too not free of cost though cheaper than asking price of the online tool ($69 < $90).

Downloaded the application and uploaded my file to the software tray. It began to repair the M4A video file and took around 10-15 minutes after the repair stopped. Here, I couldn’t preview my repaired file since the software can only allow a preview of a file having a size >= 10 MB in the demo. Again visited their website and looked for a refund policy in case the product doesn’t perform. Luckily, I found the page and registered the application which allows previewing the video before saving. In the preview itself, I came to know that my file audio-video problem has resolved. The video played after the mark of 7 minutes until the closure correctly. My video presentation just worked fine, and I saw no distortion whatsoever.

Repairing a corrupt video file, an M4A or MOV doesn't come up for free. There are many desktop and online applications available that possesses the capability to fix the video, but they won't do for a free. So, if you plan to fix a critical video choose your software wisely since you will be paying for it.