# FMod 1.05.02 Matrix Callback issues.

**URL:** <https://qa.fmod.com/t/fmod-1-05-02-matrix-callback-issues/11664>\
**Category:** FMOD Engine\
**Created:** [October 7, 2014, 7:13pm UTC](https://qa.fmod.com/t/fmod-1-05-02-matrix-callback-issues/11664 "2014-10-07T19:13:24Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![jmora](https://avatars.discourse-cdn.com/v4/letter/j/7bcc69/32.png) [@jmora](https://qa.fmod.com/u/jmora)\
**Post date:** [October 7, 2014, 7:13pm UTC](https://qa.fmod.com/t/fmod-1-05-02-matrix-callback-issues/11664/1 "2014-10-07T19:13:24Z")

</div>

I am having trouble setting up callbacks with the latest release of FMod API 1.05.02.  
In my class I have:

```
{
    private:
        FMOD_PAN_SUM_MONO_MATRIX sumMonoMatrix;
}

```

then in my class create method, I have:

```
sumMonoMatrix = dsp_state->callbacks->pancallbacks->summonomatrix;

```

And this should work since summonomatrix is defined as part of FMOD\_DSP\_STATE\_PAN\_CALLBACKS.

But when I add the plugin to FMod Studio 1.05.02 (build 58826)… It crashes every time I add it to a processing chain - specifically that the line above.

What’s going on?

---

<div class="post-metadata">

**Author:** ![nick1](https://avatars.discourse-cdn.com/v4/letter/n/47e85d/32.png) [@nick1](https://qa.fmod.com/u/nick1)\
**Post date:** [October 9, 2014, 12:43am UTC](https://qa.fmod.com/t/fmod-1-05-02-matrix-callback-issues/11664/2 "2014-10-09T00:43:18Z")

</div>

This will be fixed in 1.05.03 which will be release in the next day or two.