One America, Many Voices Act - Entitles an employee in a position requiring the use of one or more languages besides English to premium pay amounting to 5% of the employee's rate of basic pay. Declares that this requirement does not apply to an employee in a position the classification of which takes into account such language requirement, except: (1) to the extent that the rates of basic pay for the position are not at least 5% greater than the rates that would otherwise apply in the absence of the language requirement; and (2) in other circumstances as the Office of Personnel Management (OPM) may prescribe.