I encountered the error [FMOD] ChannelControl::isPlaying(00000079571AF4C0:false) returned ERR_CHANNEL_STOLEN for CHANNELCONTROL (0x7D2001D). I don’t really know where it is coming from or how to fix it.

The scene this is appearing was previously working. So I am unsure what has changed.

I am with Unity 2020.3.24f1 and FMOD Unity Integration 2.01.11
Any help with chasing down the bug would be appreciated.


ERR_CHANNEL_STOLEN means a virtual voice has had it’s channel stolen by another voice and it is now invalid. It should only come up when API Error Logging is enabled and as long as you can’t hear voices being cut off suddenly it’s safe to ignore.
If you do notice voices cutting out however you can try increasing the virtual channel count in the FMOD Unity settings. If you are still getting the error then it might be that the Max Instances setting of an event is too low and it’s channel is being stolen as a result. Such events can be identified using the the FMOD Studio Profiler. In the 3D Preview window, virtual channels are displayed as hollow grey circles.

Clicking on the hollow grey circles will open the instance in the deck:

Clicking on the arrow icon will open the event that is going virtual in FMOD Studio. On this event you can then increase the Max Instances which will prevent this error.
You should also check the Max Instances settings of any buses that this event is in, including the Master Bus.
If you are still getting the error after that, then you may need to do some optimization, but try checking the Max Instances first.

Many thanks for the in-depth explanations. I know where to look now. :slight_smile:

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