Why do you observe a triangular wave, if the outputs produce a half-sine wave? It looks like there's a measurement setup problem if the sine-waves transform into an observed triangular wave.
I'm not familiar with the CS43L22 but I'd assume that it's neither register nor address compatible so the register writes that happen in your system are ignored at best or (if it's SPI or by any chance the I2C addresses match (unlikely)) wreak havoc in the DAC setup at worst.