Do you know which models have what DAC's built into them? I read that the Kenwood Music Keg specifically has 24 bit Burr Brown DAC's. How about the OEM PB's such as Audi/VW models? Also, what is the normal method of going about tapping into the audio of the Audi/VW models that have no built in RCA's? Is this just a splice and solder situation, or is there a cleaner method of doing this.