Hi Wolfgang,
We would expect the H-sync jitter to vary during the settling period after power up but 120ns seems a lot.
There is approximately a 2.5 line delay through the ADV7403. When you measure the H-sync jitter, are you comparing the same input line to the same output line?
I'll try and set this up in my lab next week to see if I can measure the same jitter results as you have gotten with our evaluation board.
Regards,
Derek