OK.
Can you try this:
(1) Remove all PS2 BNC phono plugs.
(2) Push the four contact jack fully home into and out of the TV jack socket at least ten times (hopefully to clean the contacts and exercise the jack socket internal switch- if fitted).
(3) Connect the yellow PS2 phone plug to the TV BNC phono sockets in turn.
(4) Which connection gives you a picture (there should be no sound from the TV left or right speakers).
Can you try this:
(1) Remove all PS2 BNC phono plugs.
(2) Push the four contact jack fully home into and out of the TV jack socket at least ten times (hopefully to clean the contacts and exercise the jack socket internal switch- if fitted).
(3) Connect the yellow PS2 phone plug to the TV BNC phono sockets in turn.
(4) Which connection gives you a picture (there should be no sound from the TV left or right speakers).