error: unpack requires a string argument of length 4

I'm using the windows .exe version for 64bit systems. If I try to upload my normal GoPro video that was converted to an mp4 it gives this error and won't let me proceed.

```
---------------------------
Error
---------------------------
{Traceback (most recent call last):
} \ \ File\ "lib-tk\\Tkinter.py",\ line\ 1541,\ in\ __call__\
\ \ File\ "spatialmedia\\gui.py",\ line\ 65,\ in\ action_open\
\ \ File\ "spatialmedia\\metadata_utils.py",\ line\ 404,\ in\ parse_metadata\
\ \ File\ "spatialmedia\\metadata_utils.py",\ line\ 353,\ in\ parse_mpeg4\
\ \ File\ "spatialmedia\\mpeg\\mpeg4_container.py",\ line\ 42,\ in\ load\
\ \ File\ "spatialmedia\\mpeg\\container.py",\ line\ 96,\ in\ load_multiple\
\ \ File\ "spatialmedia\\mpeg\\container.py",\ line\ 35,\ in\ load\
{error: unpack requires a string argument of length 4
}
---------------------------
OK
---------------------------
```

Previously I've been able to export my 360 video files to mp4 using the goPro player. Screenshot attached below. I use the 4k size and HEVC type of conversion/compression. I tried exporting with H.264 but that causes an error and stops the exporting process completely(not the point). I did test with a much smaller default mp4 that I downloaded off the internet to see that the file type is working. Any solutions would be welcome, I'd prefer to not use the python install versions and continue with the .exe