The issue
On the workbench, an Amiga 600 which has a blue/green screen.. Red is missing.
And Audio isn’t working as it should.
The cause
As I inspected the board I saw very much corroded pins/solder.
The red signal is missing, so we focus on the R_out of the CXA1145 encoder. The problem was found in/after the Q231 (2N3904) transistor.
Replaced it, and whoop! colours are back again..
Bad audio!
As you can see the area around the 347 opamp, is a bit corroded. Cleaned it, and did an inventory of broken traces.. after that I reconstructed everything and audio is back again.