Briefly I used adbrite ads on my site. The support is just horendous. You get a reply maybe in a week. But that is not the worse thing. People told me that they got trojan warnings after they visited my site. And that the full page ads from adbrite are just messing up their browser.
For a well known company Adbrite to act this way, is a very stupid move. They don't care? Maybe they got too many customers.
I suggest you stop using this lousy company.