On the 7612, I’m having some problems with 12-bit 1080p input signals. The TTL output seems to become unstable and even the HDMI measurement registers are changing values. I don’t notice this issue on lower resolutions or for 8 or 10 bit inputs. On some other ADI receivers, I remember there used to be some bits that needed to be set for higher bandwidth modes, but I couldn’t find anything in the 7612 register spec.
The only register I found was IO 0x14[4:3] for DR_STR_CLK, which I set to 11b (for pixel clock > 100MHz).
Are there other registers that I'm missing?