Turner ( 2002: 227) gives unna for 2nd person singular and plural. You is found pervasively in his texts as 2nd person singular pronoun, however. Cunningham's (1992: 18) pronoun paradigm confirms the distinction between you [2PL] and unna [2PL]. Turner's texts are transcriptions of semi-structured interviews between himself and his informants. There is no indication of a politeness distinction between the two.
Source: Turner  2002: 268
Source: Turner  2002: 227