SSAO showing through my character

I'm using the built in Screenspace Ambient Occlusion effect in my game and for some reason the effect shows through my main character. It makes the character look slightly transparent, but only shows the AO effect through... so it makes patchy dark spots on my character. Can anyone tell me what can be done about this?

It sounds very likely related to this issue I had. If what happens is that the SSAO of objects behind your character are showing through it, and you're using a custom shader for your character, then it's almost certainly the same issue.