I think that a potential critique of multiculturalism is that it inevitably silences voices. It becomes practically impossible to represent every culture that has been silenced from previously Euro- centric focal points. This is not to say that "no voice should be heard because all cannot be heard." Rather, it is to point out that the simple "embrace" of multiculturalism does not necessarily address the issue marginalization. It becomes logically impossible to simply suggesting that multiculturalism solves all of the problems that a Euro-centric focus presents.
Along these lines would be how "multiculturalism" is defined. "Multiculturalism" is one that is predominantly understood as ethnic or racial notions of the good. Yet, I think that the primary focus of multiculturalism is to integrate as many previously silenced voices into the discourse as possible. This would include economically silenced voices, gender, and sexual orientation voices. This could also include the voices of different positions on the mental health spectrum. In this, multiculturalism is something seen in more than just traditional notions of culture and ethnicity.