diff --git a/v0.5/4-demos/04_sound/O-ESD_demo_04_sound.mp4 b/v0.5/4-demos/04_sound/O-ESD_demo_04_sound.mp4 new file mode 100644 index 0000000..91e0191 Binary files /dev/null and b/v0.5/4-demos/04_sound/O-ESD_demo_04_sound.mp4 differ