assets – Footstepper with Vr Unity

I have the Footstepper: Complete Footstep Solution from the unity store, and i dont get it working with the Vr,

I made the footstep material like official documentation said, Then
i put the Footstepper Setup in the ovrPlayer object.

The problem is that sometimes sound the default fallback, so i think that the colission is not detected as it suppose.

Some idea ?