hi guys, here is the deal, Just purchased my shiny 27inch imac i5 And I am looking to connect it to my speaker / amp setup I used to have my pc plugged into the amp has two wired speakers connected to it, and on my old pc, i had the amp connected to my pc via a 2XRCA to 3.5m headphone wire... I had the red and white RCA connected to the back of my amp and the 3.5mm end connected to the line out on my pc. everything worked fine.. I have just attempted the same setup on my mac however I hear nothing? I have tried both the headphone port and the one next to it on the back of the mac? but still nothing.. do i need a different cable to connect the two? connections at back of amp (no digitial input) :- speaker that connects amp to imac/ old pc :- any ideas guys?