Masuda Breeding. am I just unlucky?

[Cubonefan]

So I have been trying to breed a shiny pokemon. I have two pokes of different regions in the center (US and Korea), and have the shiny charm. To speed up the hatching process I have a pokemon with Flame Body in the party, and am making use of the Harching O-Power. At this point, I have hatched 369 eggs without a shiny. Am I doing something wrong, or am I just unlucky? I have other shinnies I want to breed this way but not sure I'm willing to go through all of this over and over. Lol

One of the two pokes I have at the daycare center is a Ditto, but I uderstand that this should not affect the Masuda Breeding method. Correct?