Gear VR / Unity / not build

Hello,

I test  Gear VR with unity 4.6.1 pro andvuforia unity-and-mobile-android-ios-4-2-3-beta-eyewearI integrate Oculus SDK 0.5.0 in the project unity, and followed the tutorial step by step.when I compile the application in unity, I have an error message:

Error building Player because scripts had compiler errors:

Assets/OVR/Scripts/OVRManager.cs(405,24): error CS0246: The type or namespace name `OVRVolumeControl' could not be found. Are you missing a using directive or an assembly reference?

Licence key is valid.

Thanks for your help