No sound from a specific bank following update

Unreal Engine
1

Hey everybody

following the latest UE5 “forced” update to version 5.5.4-40574608 we noticed an unusual behavior with event playback. All events linked to one specific bank (called in our case “SFX”) are completely mute inside the game. This happens regardless of event type (2D or 3D), mix bus // VCA assignment and playback method (triggered, dragged as ambience, etc).

All the events assigned to other banks seem to behave correctly so far.

Playback in Studio also behaves correctly.

What we tested:

  • moving events to a different bank fixes the issue
  • creating a temporary bank and assigning a sound to it fixes the issue
  • updating FMOD studio & plugin to latest available version on the website (2.03.09), does not fix the issue
  • building banks, does not fix
  • running manual in-engine validation, does not fix
  • deleting the bank from the content drawer and rebuilding, does not fix

Unfortunately we are not able to go back to the old unreal version as it doesn’t seem available for download. Also we’d much prefer recover the old work instead of migrating everything towards a new bank. We are in quite a tight spot so any help would be beneficial :slight_smile:

2

Are you getting any errors or warning in the output log?

Adding extra logging in the settings may help, by enabling ‘API Error Logging’ and/or changing the logging level to Level Log.

3

Hey Cameron

We’ll pull some logs and post them here.

Is there any more documentation aside from this page we can use as reference?

(Apologies for the beginner question, it’s our first project with Unreal integration)

4

Just the information on the Settings page.

5

We enabled the ‘API Error Logging’ and analyzed the output logs.

I couldn’t find anything specific on banks loading (they are also validated correctly), however I noticed several events being flagged as:

[2025.09.21-15.23.36:408][702]LogFMOD: ‘/Game/FMOD/Events/0.ALL/LightSwitch_Standard’ cannot be used as a UE4 asset path. Name may not contain the following characters: .. Using ‘/Game/FMOD/Events/0_ALL/LightSwitch_Standard’ instead.

6

We create .uassets for the FMOD Studio Objects so that you can interact with them in the editor, but unfortunately .uassets do not play nicely with special characters (eg. spaces).

So we replace spaces with underscores when creating the .uasset files and log it just so that you are aware. It’s not a problem but just informative.

Have you tried using the FMOD Studio Profiler to capture a session where the events linked to the specifc bank are mute? You can use it to check positions, lifetimes, parameters, volumes, instance count, etc. This can just help to make sure what you are expecting is what is happening.