Black reflections with Android/GearVR

Sphere Reflection Capture or Ambient Cubemap didn’t give me any kind of reflection with standard Materials in EC2 for GearVR.
Neither with a dedicated Cubemap nor with automatic Scene Capture. Reflections keeps being black. Have done a lot with Unlit Materials but now I need a lot of reflective metal type materials and it driving me nuts by not working.
4.13 , developing for S7 GearVR here.