So glad to have found this thread - this issue was driving me nuts.
I am new to OBS so my first instinct was that I had messed up somewhere or just didn't know how to set things up :-\
My findings are largely the same as others:
- The audio in the remuxed .mp4 crackles/clicks and is noticeably lower quality (sounds tinny) when played back in QuickTime.
- Audio of remuxed .mp4 sounds fine when played back in VLC.
- Audio of .mkv also sounds fine when played back in VLC.
- I used VLC to export the .mkv file to .m4v:
- QuickTime had no audio when playing back vlc-exported-m4v file
- VLC itself had trouble with its own exported .m4v file - it would start playing audio-only for the first 15 or so seconds and then bring up the video after 15 seconds. It's as if the first 15 seconds worth of video frames were dropped by VLC during the conversion.
Haven't tried out
@bluesnoz's suggestion of using FFmpeg - will do so tomorrow.