I am not tooooo worried about it because I have a 480> sbm-1> d8 copy also, so I was thinkinh of making a matrix of the sources. With that, I think that the fluctuations will be un-noticable.
Also, is there a quick and dirty ratio for matrix-ing? I was thing SBD/AUD 60/40, but damn, those 480's sound so good!!