I've had the same problem on a similar board that I had, it also had a mod chip but eventually installing a PS1PSU ended up frying the thing and now I'm figuring out how to repair it.
I suspect the mod chip interferes with how the CD-rom reads. I bought multiple KSM-440BAM drives to try to solve ...

What you should be using to lubricate the tracks and rails of a cd rom drive that has plastic gears is,
Tamiya 87099 Cera Grease Hg.
https://m.media-amazon.com/images/I/41nS7zqq3kS._AC_UF894,1000_QL80_.jpg
This stuff is formulated in Japan and used for small gear assemblies for micro RC Cars that ...

Does anyone have this strange issue where the MultiAV port doesn't skip audio but the RCA plugs do?
I'm using the SCPH1001 as a CD player currently and I am trying to figure out why whatever I do to the trim and bias the cd keeps on skipping. I've already replaced the drive with a KSM-440BAM and ...