Can you guess the race?

Now that it is football season I have a little game that I play when I watch a televised game. Some people may thing that it is racist but I honestly don't think it is racist at all, if anything, I think that it has do to with America's cultural heritage. 

The game is to guess which race that the interviewed player is without looking at the TV screen.  In other words, can you tell what a person's race is by listening to them speak?  I've begun to try this with most voices that I identify as being spoken by an African-American, an Hispanic, an Asiatic, etc., speaker.

I wonder why the African-American has such a distinctive style of speach as compared to an African born and raised in the UK or a native African.  Often, I am unable to understand the speach of an African-American, whereas the speach of other Africans is easily understandable.

Why is this, I wonder.  All of these athletes are currently enrolled in college and they have to have passing grades in order to be able to compete, or, if they are professionals, then a large percentage of them have graduated from college.  And yet, I can't understand them when they speak.

To those who think this is racist, I would say that their speach has very little to do with genetics, and has everything to do with their cultural surroundings.  Remember back a few years ago when the controversy of euphonics arose.

I wonder what the status on euphonics is these days, anyone know?