Matrix creator inhibits I2C

I have a Creator on a Raspi 4 - 4mb. I cant use I2C with the same software that runs on a matrix voice (no ESP32). Same setup, same software , same SD card, just changing between the 2 matrix cards.
Does an Matrix tech know why? I would prefer to use the Creator if I can with this robot application.
Thanks in advance for your reply.

Hi there @rickmini

What are you using those pins for?

The MATRIX Creator and MATRIX Voice don’t use those pins, however, you need to modify the FPGA Verilog code in order to use them. Did you do this for your MATRIX Voice?

Im using i2c on the raspberry4 to control a time of flight sensor and an Oled display. using python3 and the adafruit blinka libraries. All things being equal, if i swap between the Creator and the Voice (no ESP32) my code works with the Voice and i get an address error when i use the Creator. It seems that the creator is causing a conflict with I2C. Does the creator use I2C to talk to the Raspi?
Im not familiar with the FPGA Verilog code, can you point me in the right direction?
Thanks