I have a question about ADV7390.
It turns out that the ADV7390 supports NTSC M.Does it also support NTSC J?
As per ADV7390 specification, I beleive it can support only NTSC M. Have you tried with NTSC-J ?
The main difference between NTSC-M and NTSC-J is that the black level,
NTSC-M Black level: 7.5IRE NTSC-J Black level: 0IRE.