I have a close friend with the last name Kline. But I read so much fanfic and Bernie baby is often in it, that I type her name Klein, often on official documents.
American's don't have as many specific ways to say "o" as the Scandinavians. To us Jonathan, Jonathon and Johnathon would all sound the same. When I was on a tour of Norway our guide try to tell us how to say the different "o"s, but my ear simply couldn't differentiate them. I guess it is something you have to learn in infancy.
Artemis