FYI. Denafrips is still working on a fix for I2S in old DDCs that are not compatible with the DAC running updated firmware. It seems more complicated than updating DAC. Here is what Vinshine tech support said this morning:
"The latest DDC are already installed with the latest firmware update which includes similar i2s optimization as the 12th firmware for the DAC. As a result, the i2s will be compatible.
Regrettably, the firmware update process for the DDC is more complex compared to the DAC, primarily due to limitations imposed by chipset variants.
The firmware update process may not be straightforward, and it could potentially require a programming tool. This could make it more challenging for customers to perform the update on their own.
Consequently, we are still exploring for a feasible solution to get this fix. "