We claim the ornamental design for a head mounted audio-visual display system case insert, as shown and described.
FIG. 1 is a perspective view thereof in a first open configuration with the case depicted in broken lines;
FIG. 2 is a perspective view thereof in the first open configuration with the case and components of a head mounted audio-visual display system contained in the case depicted in broken lines;
FIG. 3 is a top view thereof in the first open configuration with the case depicted in broken lines;
FIG. 4 is a top view thereof in the first open configuration with the case and components of a head mounted audio-visual display system contained in the case depicted in broken lines;
FIG. 5 is a perspective view thereof in a second open configuration with the case depicted in broken lines;
FIG. 6 is a perspective view thereof in a third open configuration with the case depicted in broken lines;
FIG. 7 is a top view thereof in the third open configuration with the case depicted in broken lines; and,
FIG. 8 is a top view thereof in the third open configuration with the case and components of a head mounted audio-visual display system contained in the case depicted in broken lines.
The broken lines depicting the case and various objects storable in the case for head mounted audio-visual display system are included for the purpose of illustrating environmental structure and form no part of the claimed design.