easy people, little problem that i could do with getting rid of. basically when i load up logic my monitors start giving out a high frequency hiss..... it's really really quiet and i've lived with it for ages, but it's starting to do my head in! as soon a i turn logic off the hiss disappears. ive got a Saffire 6 USB DI, with a pair of KRK Rokit 8" & a pair of 5", im using a 1/4" jack form the Saffire into a phono into my speakers if that helps???!?!?!?!?!?!? Thanks.