Assassin's Creed II MXAO issue

So I've been making some presets for AC2, which is my favourite game of all time, but is looking a little outdated. With just about every effect working fine, I am having an issue with MXAO. Everything is practically transparent when it is turned on, as the ambient occlusion can be seen through walls. This is a massive shame because apart from this, the game looks absolutely stunning with AO. Does anybody know a fix?

That looks more like a depth buffer issue, probably it doesn't contain the depth data of certain objects and then takes the depth data of those behind.
@crosire?

I guess so. You may want to check what the depth buffer looks like (DisplayDepth effect).

Thanks for replying guys. I turned it on and it looks like this:

i.imgur.com/IRymERr.jpg (on)

i.imgur.com/HvYNZ3p.jpg (no effects enabled)

Does this mean there is no way of getting past this issue?

Do you know of any other ways this issue could be delt with? @crosire

Yeesh, there's a lot cut out of that. You'll probably just have to use the game's AO and some contrast adjustments.