Behringer p16 issue

New

Hey all I have a weird problem with my p16s related to the P16-D  


I have power coming from the P16-D to all my P16-Ms but only ultranet to half  


channels 1,2,5 & 8 have power and ultranet  and 3,4,6 & 7 are recieving no ultranet signal


can anyone help!?