Constant Perform. Spikes "VR.WaitForGPU" & "Unaccounted time between: camera.render and GUI.repaint"

I keep getting spikes periodically when using the Steam VR plugin. It's around every 2 seconds or so. It started randomly, pretty much after I updated to Unity 5.5 but I checked in 5.4 and now I'm getting the same issue... I also tried the latest patch of 5.5. I'm even getting this issue with a scene that has nothing except the "[CameraRig]" prefab from SteamVR.

I checked if it was a HTC Vive issue but I played a game and it didn't have that lag every 2 seconds.

Here is the profiler of the...

Constant Perform. Spikes "VR.WaitForGPU" & "Unaccounted time between: camera.render and GUI.repaint"