I don't think their is a right it wrong answer, it depends on how you feel about it and how much you think it'll affect your role. Personally I would say something, if they didn't notice/realize in the interview - giving them a heads-up may be helpful if you have a bad day. I've found being more open about it with coworkers puts everyone more at ease of they don't understand something I say. Callers won't know this, but your co-workers being aware can help.