Chris,
Thanks for taking an interest in my setup, yes I have +/-10V applied. The setup with the factory original boards works fine. Yes I am looking at I/O the I2C expander. I soldered wires to board via's to get access to Reset and SYNC signals. MFLAG is floating, any idea if that could be an issue? I thought I monitored it and saw no activity on the working setup, but as i type this, I think best I tie it off to be sure. PMODE is hardwired low on my board, again I monitored it for activity on the working setup and saw none.
Perry