Folks,
The subject pretty much says it. Are there any that can at least be coaxed into DC input and output by disabling internal cancelers and such? Should not be too drifty. The digital interface doesn't matter much, USB, SPI, whatever. Preferably not I2C but even that would be ok.
16 bit would suffice. Of course, more is better. Input to output synchronicity is important, as usual. Also synchronicity between the stereo input channels.