Audio Mixer Output Checker

Every AudioSource has an Output field. Unity leaves it empty by default. And an empty Output means that sound never enters your mixer at all.

So your Music, Ambient and SFX sliders do nothing for it. The player drags "Sound effects" to zero, and it keeps playing at full volume.

Nothing warns you. No console message, no yellow icon, no hint in the inspector. The sound works perfectly - it just ignores the settings your player chose. The only way to catch it by hand is to test every single source against every single slider, which nobody does. So it ships.

Audio Mixer Output Checker finds all of them and routes them in one pass.

THE PREFAB PART, WHICH IS WHERE THE TIME GOES

Most sounds live in prefabs, and a prefab is dropped into scenes many times over. Listing every scene copy would mean creating a pointless override on each one - and leaving the prefab itself still wrong.

This tool scans every prefab in your project and lists the prefab, not its copies. One write fixes every copy of it, in every scene. The window tells you how many copies it hid, so you can see the leverage.

Three cases, told apart automatically:

- the prefab asset, fixed once for all its copies;

- a plain scene object that belongs to no prefab;

- a scene copy whose Output was cleared by hand on that copy alone - fixed on the copy, exactly where it belongs.

IT PROPOSES, YOU DECIDE

No tool can know that sfx_042 is a footstep. What it can read is the clip name and how the source is set up, and put a sensible group in the popup on each row.

You define the roles yourself: a name, one of your mixer groups, and a list of keywords. Music, Ambient, Voice and Sound effects come as defaults - add, remove, rename and reorder them until they match your game. Order matters, and the arrows are there for it: a narrow role like "Voice" must sit above a broad one like "Sound effects".

Keywords are checked before anything else on purpose. A line of NPC dialogue is a 3D source placed in the world, but it is a voice, not an effect.

When no keyword matches, three fallbacks you set decide: 3D sources, 2D sources that loop on awake, and everything else.

A role with no group assigned leaves its rows empty and is never written. Nothing goes anywhere at random, and nothing at all is written until you press Assign.

WHAT YOU GET

- Scans every open scene plus every prefab in the project, inactive objects included.

- One row per source: object name, 2D or 3D, the name of the clip inside it, the suggested role, and where it lives.

- Select pings it in the hierarchy or the project.

- A group popup per row, pre-filled, editable.

- All -> group to set the whole list at once, because sound effects are usually the overwhelming majority.

- Your mixer, your roles and your options are remembered between sessions.

- Ctrl+Z reverts the scene part in one step.

HONEST NOTE

Every source this tool lists already plays correctly. Nothing is broken, nothing is silent, nothing crashes. And if your master volume is built on AudioListener.volume, it still reaches those sources today, because it is applied on top of the mixer.

What you gain is that your per-channel sliders finally reach every sound in the game. If you do not use an AudioMixer, this tool has nothing to do for you.

GOOD TO KNOW

Only the scenes you have open are read - scanning every scene would mean opening and closing each one, which invalidates the list you were reviewing. Prefabs, on the other hand, are always scanned project-wide.

Prefab changes are written to disk like any other prefab edit, so they follow your version control rather than the undo stack.

COMPATIBILITY

Unity 2022.3 or newer. Editor only: nothing ships in your build. No third-party dependencies. Built-in, URP and HDRP.