# Trigger Box Change Parameter

**URL:** <https://qa.fmod.com/t/trigger-box-change-parameter/19938>\
**Category:** Unreal Engine\
**Created:** [March 6, 2023, 7:06am UTC](https://qa.fmod.com/t/trigger-box-change-parameter/19938 "2023-03-06T07:06:39Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![daniellumertz](https://avatars.discourse-cdn.com/v4/letter/d/7cd45c/32.png) [@daniellumertz](https://qa.fmod.com/u/daniellumertz)\
**Post date:** [March 6, 2023, 7:06am UTC](https://qa.fmod.com/t/trigger-box-change-parameter/19938/1 "2023-03-06T07:06:39Z")

</div>

Hello everyone! I am making a lever and I wonder what would be the best practice to change a parameter on a FMOD actor in my level, if I should use class blueprints or do it at the level blueprint.

At the level Blueprint it is using this whenever a player passes by the triggering part

 ![image](https://canada1.discourse-cdn.com/flex036/uploads/fmod/original/2X/3/3a561e0285c77339683924d064f810e9303e6f5f.png)

I made this into a function so it look like this

 ![image](https://canada1.discourse-cdn.com/flex036/uploads/fmod/original/2X/c/cda475b36bdb4d907f3d9533e0801232e648f5a9.png)

Its kinda nice and working! But as there will be more and more and more events to trigger I think the level blueprint will be cluttered!

So I wonder for this case the best practice is to create a Triggering class blueprint, and add the code there ? Are there some examples of how I can reference my FMOD actor with the audio component? Should I do something like Casting the level for it?  
Thanks I am pretty new, trying to find the best practices !

---

<div class="post-metadata">

**Author:** ![daniellumertz](https://avatars.discourse-cdn.com/v4/letter/d/7cd45c/32.png) [@daniellumertz](https://qa.fmod.com/u/daniellumertz)\
**Post date:** [March 6, 2023, 7:43am UTC](https://qa.fmod.com/t/trigger-box-change-parameter/19938/2 "2023-03-06T07:43:24Z")

</div>

Ah ok, so what I did was to put the FMOD Audio Component inside a BP class, in this case I put inside the player itself.

Then created a BP class for the triggering box. Added a variable with instance editable ( so I can change the value per instance). And with this BP

 ![image](https://canada1.discourse-cdn.com/flex036/uploads/fmod/original/2X/6/6490dc7be1ea6b31303bd1a20cc79f8bf830522a.png)

It is better now as it wont pollute the level BP