I'm thinking of taking the optical output from my motherboard and plugging it into a Tascam US-366 optical in. The specs on the Tascam say it's 192K/24 bit compatible. The outputs of the Tascam would then go to a Parasound PHP-850 preamp and then to the amp section of a Mac 1900 receiver which drives the headphones. Has anyone had experience with the Tascam when used in this manner, or perhaps can anyone suggest a better solution in the same price range? I am currently using the Radio Shack DAC for this purpose.