Hello,
What's the state of DAC80508's SDO pin while the VDD (analog supply) is off but the VIO is on? It looks the SDO level is still High and disturbs SPI communication of the other SPI slave devices on a shared SPI bus.
In the system, the DAC80508's VDD is turned off when the system is put into a power-save mode. Hi-Z is expected at the SDO pin in this mode.
Best regards,
Shinichi Yokota