[Version 5.4] SteamVR Vive Transform Hierarchy Changes

Hi all,

I've recently upgraded to 5.4 and ever since the upgrade, the SteamVR CameraRig prefab changes its hierarchy on play. The prefab is as below:

• [CameraRig]
  • Controller (left)
  • Controller (right)
  • Camera (head)
    • Camera (eye)
    • Camera (ears)

However, upon pressing play on any project (even a freshly made one), the transform hierarchy changes to this:

• [CameraRig]
  • Controller (left)
  • Controller (right)
  • Camera (eye)
    • Camera (ears)
    • Camera (head) - disabled.

Can anyone shed some light on why this happens? Is it intended, or is it a bug?

Thanks in advance.