AO is disabling my depth buffer [2.0.3]

I've tried everything, I don't know what's going on.

I used to be able to have AO and DOF at the same time. Now it refuses to, no matter what I try. It's one or the other. I used to have F8 configured to toggle both effects, then something went wrong and I had to assign separate keys. Then I changed that back and now it's one or the other. I know that I'm being vague here, but the tool isn't helping me one bit and I'm really fuckin' tired of trying and failing to fix this issue.

So are there any known conflicts between these two filters?

Thanks

*bump*