ambient occlusion maps not working for me in Unity 5

For some reason, the occlusion map is not doing anyting in Unity 5.
I use a greyscale jpg image, tried it on the standard shaders, standard specular setup, UBER shaders, it just doesn’t do anything, all other maps work perfectly.

tried gamma/linear to see if somethings up there, no dice, tried to use forward rendering and deferred, no dice.

Anyone has any idea as to why the maps won’t work ?

right now i have to use SSAO to get some AO going on, but i need those shaders working.

Remember that occlusion maps won’t affect direct lighting (such as realtime spotlights / directional lights / point lights), but rather indirect lighting, such as bounced light in baked light maps, or ambient light (which Unity calls Environment Lighting), pictured here:

95520-environ-lighting.jpg