I have the MA Radius R90 Av12 package hooked up to an Onkyo 875. I did the audyssey setup but it gets it wrong everytime, presumably down to my room acoustics etc, so i have to do it manually which is a pain beacuase i dont know if i am getting the best out of my system. I have set the speaker crossovers to 90khz and 90khz for my sub too. Is this right?