Latest master has issues loading in audio files

![image](https://user-images.githubusercontent.com/48299282/186415713-cc275a45-fa40-49b6-8003-d1a23b7fc53b.png)

It hangs here forever and then eventually gives the error `At least one required element has not been found`

**Basic command line to replicate the error**
`"MP4Box.exe" -add "E:/Legion.2010.BluRay.1080p/Legion.2010.BluRay.1080p_out.h264#1:name=:lang=und:fps=23.976:ID=1" -add "E:/Legion.2010.BluRay.1080p/audio.ac3#None:name=:delay=0:lang=und:ID=2" -new "E:\Legion.2010.BluRay.1080p\Legion.2010.BluRay.1080p_out.muxed_output.mp4"`

**Sample of the audio file**
https://www.mediafire.com/file/724dlbd6qlop8ra/audio.ac3/file

If I don't add the audio the file mux's just fine. Also if I use the older 1.0.1 release of mp4box.exe it accepts the input flawlessly

Windows 10 x64
Bug when importing audio files with latest master
This is a GitHub Issue
repo:gpac
owner:gpac
Title : Bug when importing audio files with latest master
Issue date:

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Latest master has issues loading in audio files

![image](https://user-images.githubusercontent.com/48299282/186415713-cc275a45-fa40-49b6-8003-d1a23b7fc53b.png)

It hangs here forever and then eventually gives the error `At least one required element has not been found`

**Basic command line to replicate the error**
`"MP4Box.exe" -add "E:/Legion.2010.BluRay.1080p/Legion.2010.BluRay.1080p_out.h264#1:name=:lang=und:fps=23.976:ID=1" -add "E:/Legion.2010.BluRay.1080p/audio.ac3#None:name=:delay=0:lang=und:ID=2" -new "E:\Legion.2010.BluRay.1080p\Legion.2010.BluRay.1080p_out.muxed_output.mp4"`

**Sample of the audio file**
https://www.mediafire.com/file/724dlbd6qlop8ra/audio.ac3/file

If I don't add the audio the file mux's just fine. Also if I use the older 1.0.1 release of mp4box.exe it accepts the input flawlessly

Windows 10 x64
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