Fmod Studio Event Emitter & "Max Instances"

We have a specific sound that we have set “max Instances” to 4, and in the profiler we are noticing that there are way more than 4 instances of that sound playing. The sounds are being automatically played via “Fmod Studio Event Emitter” when it hits a collision volume.

I am unsure if the “Fmod Studio Event Emitter” abides by the “max instances” parameter in the event. Can someone shed some light on this? The number of “Fmod Studio Event Emitters” in my image below is 38, and are all triggering at once as a test – they are also all playing w/ 38 instances (even though I have it set max instance =4)


You’re looking at the event’s “voices” in the profiler, which is not synonymous with an event’s “instances.”

New voices are created whenever an instrument is triggered or selects a playlist entry to play, so one event instance can easily have multiple voices if its content requires it.

To view an event’s instances in the profiler, click on “Instances (Self)” in the profiler window’s transport bar.

Hi Joseph, in the post I attached an image of the “instances” (which is 38). Attaching it here in case it didn’t go thru initially

I am not sure why it is giving me 38 instances in the profile when i explicitly set it to max 4 instances in the event in the Fmod Project 2.01.07

Hi @joseph , can you please take a look? We are having alot of issues with fmod currently with sound cutting off due to too many instances at once.

Did you try with another steal option than “oldest”? Maybe your event is triggered 38 times at the exact same time and FMOD is not able to determine the “oldest” instance to steal?.. Maybe try virtualise.

Thanks, but the behavior we really do want is “oldest”, not virtualize. I am wondering if this is a bug with fmod ignoring MAX INSTANCES ?

I am unable to reproduce this issue. When I create a test project in Unity that attempts to play multiple instances of the same event, whose ‘max instances’ is set lower than the number of instances than Unity is attempting to play and whose stealing mode is ‘Oldest,’ the event’s “max instances” property is respected.

There must therefore be some way in which your game that differs from my test project, but I am unable to identify what it is without seeing it.

Have you tried rebuilding the banks, just in case it’s a bank synchronization issue?

Can you let me know what version of unity and fmod (and fmod package) you are using?

I was able to reproduce the issue, I’ve created a very simple repro case and uploaded a Unity Proj + Fmod project repro case here (using Unity 2020.1.8f1 and fmod 2.01.07):

Also made a video showing the bug: