I found the Crystal CS8405A at Newark electronics if anyone is interested. They were something like $4.50 each. If I go ahead and build a digital out interface, would anyone else be interested in purchasing one? What would you prefer, optical or coaxial? I would prefer optical due to its immunity to noise, but if all the headunits have coax inputs, that's what it will be. The less circuitry, the better.

Stu