I know that this might be a little hard to answer but I would like to give it a go anyway.
I had a stm32f756 MCU connected to a adv7511w HDMI transmitter. Everything worked great and I get great picture.
However, when I changed MCU to stm32f767 (larger cache) I get problems with the picture as seen in the attached video. Are there anyone that can give me an educated guess what the problem is here? could the pixel clock be out of phase somehow with the video data ?