external CODEC for A13 Audio

[Matthias]

since the internal CODEC of the A13 only has a mono input (!?), it would be interesting to connect an external one
but it does not offer I2S (!?) or is it just not documented?
it seems possible to convert one of the SPI to work as I2S, but not simple...
http://www.ti.com/lit/an/slaa449a/slaa449a.pdf
http://www.altera.com/literature/an/an487.pdf

any ideas, suggestions, experiences?
thank you
Matthias

[olimex]

my suggestion is to wait A10 it have I2S and will be easier to use it instead these add-on ICs