No Green from PC Engine AV Booster

[OfficerAxelStone]

Hello,

I recently acquired an AV Booster for my CoreGrafx:



However when I connect it to my television using a Mega Drive 2 RGB scart I do not get Green.


Red, Blue and Sound are all working as they should. I've tested the cable on a Mega Drive and it works correctly.

If anyone has any ideas it would be very much appreciated

Thank you