X3D version 4.0 was approved by Web3D Consortium and ISO in 2023. X3D version 4.0 offers many new features including interoperability with HTML5, glTF 2.0 Physically Based Rendering (PBR), and Web Audio API. Correct url for X3D file should appear in <meta name='identifier' content='https://someAddress/somePath/FileName.x3d'/> Missing X3D scene description in meta tag, should appear as <meta name='description' content='topic sentence plus good summary'/> It is good practice to identify editor(s) used, for example <meta name='generator' content='X3D-Edit, https://savage.nps.edu/X3D-Edit'/> <Sound DEF=''/> location='0 0 0' has height of sound ellipse centered on ground plane, consider changing location y-value to 1.6 in order to match typical avatar height (in meters) <AudioClip DEF='Click'/> url array address(es) missing online http/https references (url='"../resources/chandubabamusic1.wav"')