Hi Itamar,
I appologize for the delay.
Clocking is very important for the SPI to work properly. Have you probed the SPI lines to make sure that the signals are meeting the clocking requirements on page 20 of the datasheet?
Is there any command/layout differences between the devices that are working as expected and the devices that are not working?
There is no specific order of setting the registers to initialize the device. The PCM1780A has a clock manager that is operated off of the SCKI clock. I don't believe there is a way to read the registers in SPI, but I will get back to you on that early this week.
Regards,
~John