Kinect disassembled but where to assemble this part in?

Hi,

I bought a faulty Kinect sensor from eBay.

While disassembling it, I found a loosen small copper disc inside the motorized stand. Could you tell me please, where to put it in? I cannot find it in your Disassembly Guide but I see it in the parts overview picture.

Please refer to this image where I marked the part.

https://www.box.com/s/ob8fvr3enmzfymdn3a...

Any help is appreciated.

Thank you very much!

Best regards,

cy2u5