Hi Ahbie,
Many thank for your reply.
We will have a try to change R109 (56R) to 15R at first.
What's more, In the previous exisiting actual circuit, R116 was NC, and the ADA4656-3 R/G/B output were connected directly to a video processor behind (do not via a cable), maybe the series resister R127/ R160 / R156 75ohm could not be removed.
regards,