I discovered, after many many hours, that programming the EEPROM thru the DSP on the Master Control port only works after the chip is rebooted. The problem occurs after a real-time code download on the slave port which apparently pulls the master control port I2C lines low and holds them low. This problem appears to be on going for quite sometime.
Sigma Studio cannot program the Master port connected EEPROM on the I2C bus since the pins are held low by the ADAU145x chip. There is no real-time error checking through the DSP so it will fail forever and happily show a bogus progress bar.
To make it work you perform a regular download and then reboot the ADAU145x chip. After this reboot the Master I2C lines are no longer held low and you can now perform a program thru DSP.
Since this will annoy the hell out of everyone, I'm posting here but please fix this error ADI. Is it a silicon error or what since many previous Sigma versions do the same thing?