Just for the record.
Fixed the glitching CDROM2 now. Worked OK when cold but a bit shaky when warm. Some games did not even want to start when it was warm.
Changed the 4.7uf caps, three of them had very bad values and one didnt even charge up at all.
After that the CDROM2 became stable.
Seems like the 4,7uf ones are the most likely to fail?