Well, if there's a vowel sound there, and maybe it's a Southern thing, I don't know, but I'm not hearing Mick. I'm hearing something more like "Muhk," but that's not entirely accurate either. A lot of people say "Mack" as if it's spelled M-a-c, but mostly, I don't really hear a vowel, or if there is, it sounds more like a "u". Can't say I've ever heard Christian MickBride, but almost everybody says Reba MackEntire.
Anyway, I interviewed her about 3-4 years ago, and while we didn't discuss the pronunciation of her name, her rep pronounced it: Ma-Kell, and when I pronounced it that way during the interview, she didn't correct me.
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"I got a bad feeling about this."
- Han Solo / Indiana Jones