Yep same problem here : got an XFI Titanium and a Z906 5.1 surround system and the game is running ilike a 2.1... What a shame... This is the same problem as in ARMA 2 long time ago where it took them many years to fix this and some months to fix it in ARMA 3. So the question is : "how long it will take them to fix it for DAYZ ?" Many years I guess if they do like the optimization of the game...