I have 3 ISO rips of DVD with basically music on them, all Steven Wilson. I don't even think they are DVD-A. Deadwing In Absentia Lightbulb Sun The first 2 on the Z9X. None of the buttons work. Page next or Prev. Audio, subtitle all ignored. Even stop doesn't work, you have to press Home to stop it The last one the buttons work fine I have a Dune 4K I and even an ancient D1 and they all play perfectly. I just tested all 3.