I've searched the forums and elsewhere but haven't really found this answer so please indulge me... My Mac Pro has just arrived and, so far, I'm very happy with it. I'm amazed with how easy it was to set up and to add my three additional hard drives. I was dumbfounded, however, to find that my Klipsch 4.1 speakers apparently won't work with it (well, at least the rear ones)-- the Klipsch has two speaker plugs: one for the front and one for the rear. Is there a cost-effective way to get my 4.1s into action that will also let them work with Windows gaming? I saw that Griffin solution, but I don't think it will work for Windows also. Is my best bet to simply buy a new set of speakers that use the optical outputs? I'd hate to spend the money, especially considering I'm otherwise happy with these Klipsch. Thanks for your input.