My Scottish last name has a double "L" in the middle of it. When I lived in an area with a high percentage of Spanish-speaking people, I tended to spell it out more than usual. In my name, the double L is pronounced as an L. In Spanish, the pronunciation is completely different. I'd say my last name and then start to spell it. I'd get a lot of surprised faces once I hit the "L, L," part of it.
But I tend to spell it out most of the time when I'm not in Home City, because there's just no way to know there are 2 Ls in there from the pronunciation of it.