Well I don't know what to say really...so here goes: I have also the Logitech Z-5500 speakers like the OP said, and they are connected with an optical cable to an Asus Xonar DX sound card. Running Archlinux x86_64 with (linux-ck-core2 optimized kernel) on a Q6600 / Asus Maximus 2 formula with an Nvi...