Oculus Ambisonics in Unity drops audio volume in one area as you turn your head?

I’m using the pseudo 5.1 technique as described the fmod documentation where I have added two silent channels to the AmbiX file, and added the Oculus Ambisonics effect on the master track. Both FMOD and Unity are set to 5.1 surround, and in Unity i’m using the oculus spatializer.

However in Unity, when I turn my head there is one area where the audio just dips in volume. Once I move past the area the audio returns to normal volume.

Has anyone come across this/know how to solve it?

Using Unity 5.6 and FMOD 1.09.03

Make sure you have the latest Oculus SDK and dll’s.

If that doesn’t change anything, you will have to contact Oculus about issues with their plugin.