Do you ever get the feeling that perhaps some machines are rigged or otherwise modified in software or hardware to pay out less than they are supposed to? In the world of gaming/gambling, it can be very difficult to find honest people sometimes. I'd make a pretty good assumption that there are machines out there that have been modified to line some pockets. I'm not suggesting that the machine you have is even such a beast; maybe you are just really unlucky or for some reason you have a terrible time eye shooting on the Azteca

In any case, sell it and buy yourself a machine that's not cursed!