# Unity 4 crashes when system.createChannelGroup is used

**URL:** <https://qa.fmod.com/t/unity-4-crashes-when-system-createchannelgroup-is-used/11732>\
**Category:** Unity\
**Created:** [November 26, 2014, 3:59pm UTC](https://qa.fmod.com/t/unity-4-crashes-when-system-createchannelgroup-is-used/11732 "2014-11-26T15:59:21Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![JeromKid](https://avatars.discourse-cdn.com/v4/letter/j/cc9497/32.png) [@JeromKid](https://qa.fmod.com/u/JeromKid)\
**Post date:** [November 26, 2014, 3:59pm UTC](https://qa.fmod.com/t/unity-4-crashes-when-system-createchannelgroup-is-used/11732/1 "2014-11-26T15:59:21Z")

</div>

Using this piece of code:

```
using UnityEngine;
using System.Collections;
using FMOD;

public class punch: MonoBehaviour {
	
FMOD.RESULT result;
FMOD.System system;
FMOD.ChannelGroup channelGroup;

void Start () {

	result = FMOD.Factory.System_Create (out system);
	result = system.createChannelGroup (null, out channelGroup);
   }
}

```

crashes Unity 4 on Mac and Win7(x64), telling “access violation” takes place.  
The “system.createChannelGroup” line is the one causing crashing as I figured.  
I’m lost!

---

<div class="post-metadata">

**Author:** ![JeromKid](https://avatars.discourse-cdn.com/v4/letter/j/cc9497/32.png) [@JeromKid](https://qa.fmod.com/u/JeromKid)\
**Post date:** [November 26, 2014, 11:06pm UTC](https://qa.fmod.com/t/unity-4-crashes-when-system-createchannelgroup-is-used/11732/2 "2014-11-26T23:06:30Z")

</div>

Figured one this one by myself, I had to call _init()_ on _system_ first before using it with _createChannelGroup_.

```
result = FMOD.Factory.System_Create (out system);
result = system.init (32, FMOD.INITFLAGS.NORMAL, extradriverdata);
result = system.createChannelGroup (null, out channelGroup);
```