Talking differently to black people

[miajag81]

At work today I had to call the Philadelphia Pension Office to get some information for a client. I found myself talking to a woman who, from the sound of her voice, was almost certainly African-American. I was repeating back the address she gave me, made a mistake, she corrected me, and instead of saying "oh, my mistake" I said "aw, my bad." I NEVER say this. I have a feeling I subconsciously was trying to sound "hip" or something, I have no idea why. Does anyone else ever find themselves unconsciously making stupid little changes to their language or behavior when talking to someone of a different race/culture?