Not sure if this is the correct forum for my question , but here goes : I have some Mission 753s and Cyrus 7 Amp and was hoping to link up my Mac G4 Powerbook to play my ripped cd's and internet downloaded mp3s via i-tunes. However i'm being warned by Mission that this may damge the speakers if played at high volumes for a lenght of time. Is there any recommended way of playing music from my powerbook i-tunes at party-level volumes for hours at a time without damaging kit? Would it make a difference if i connected the powerbook to the Amp via an i-mic line out instead of directly from the headphone jack ? Do i need some sort of sound card?