AO pass render issue

[SonyBoy]

I'm having a very strange problem with my AO pass, which is comping with some inexplicable results. See the attached image. I'm getting this result in both Ae and Photoshop. There is nothing in the alpha, there are no masks or mattes or anything that could be causing this, and there isn't even anything in the model that corresponds to the brightened area in the center of the glass. I'm at a total loss. These renders are long and expensive so this is a real problem right now.

Also, for some reason these renders are also not comping properly with render elements, with the refraction pass apparently adding additional value where it shouldn't in the glass that's visible here.

I'm using Maya 2020 and Vray 5.10.22.

[SonyBoy]

OK, I have traced this issue once again to the "Affect All Channels" setting in the glass shader's refraction settings. Wish I had a buck for every time this option has given me headaches, and again I would like to understand why the implementation of this cannot be improved so that there is more control over which channels refractions affect. In particular, the fact that this setting has to be turned on to get refractive mattes generated immediately means you're obliged to render second passes to get e.g. a clean alpha or prevent problems such as this one. Vray is a great renderer, but this particular attribute seems to cause users endless problems and confusion.