I can't see where people get off saying that some way people choose to pronounce their name is affected, and some other way isn't. Names change, because you get used to accepting the way that people around you insist on pronouncing your name, and Americans seem pretty keen on pronuncing names the way they look like they should be from the spelling - as in Wagner, pronounced Wagg-ner instead of Vahg-ner.

But actually I think that, if you propnounce Colin in the Cawlin way, (as against the English Collin way of saying it), but do it in a Jamaican accent, you get something pretty close to Kohlin.

I'm constantly having my name mispronounced, and I'll answer to either version. Swearing under my breath when I spell it out and some shop assistant says "Oh, you mean McGrath" (pronouncing it with the "th" sounded, the way I don't.)