Is it possible to control audio media in USDZ (i.e. pause, skip, load new audio file) with a scene / behavior (using Reality Composer or other tool)?
Currently Reality Composer does not support this. This sounds like a great feature request and we would appreciate if you can file feedback through Feedback Assistant.
If you are willing to jump into code…
You can use the AudioPlaybackController returned from the playAudio API to play, pause, etc. You can also use AudioFileResource to to add / replace audio on entities.