The "unity 3d sound not working" error can be caused by a few different factors:
Audio Source or Listener Issues: Your game object may not have an audio source attached to it, or there might not be an audio listener in the scene. An audio source is necessary for the object to make sound, while an audio listener (usually attached to the player or main camera) receives the sound.
Incorrect Audio Clip/Format: The audio clip connected to the audio source might be in an incompatible format, null, or corrupted.
Volume Settings: The volume level in the audio source, mixer, or system could be set to zero.
Muting or Pausing Issues: The audio might be accidentally muted or paused in your code.
Audio Import Settings: The settings for your imported audio file, like compression, could be incorrectly configured.
Here are potential solutions for the "unity 3d sound not working" error:
Check If Audio Source and Listener Exist: Ensure you have an audio source attached to the game object that should produce sound and an audio listener somewhere in the scene.
Validate Audio Clips: Make sure the audio clip attached to your audio source is in a compatible format and isn’t corrupted. Reimport the audio file if needed.
Adjust Volume Levels: Verify the volume on the audio source, mixer, and your system is not set to zero.
Review Your Code: Look over your code for any unintentional muting or pausing of the audio.
Check Audio Import Settings: Confirm that your audio file's import settings are correctly configured. For example, the audio compression format should match what is appropriate for your platform.
Update Unity: If none of above solutions work, try updating your Unity to the latest version as some older versions contain bugs related to audio.