I've notice random disc read errors since around rev 171.
We just got one on The Fairly Oddparents: Breakin' Da Rules and we had one the other day on Super Mario Sunshine. Seems like this has come and gone with different revs and the errors seems random. Previously it used to error on Sunshine when exiting a level.
If I can reproduce the error, I'll add more to this to see if maybe we can figure out what causes it. They are shrunk but have played fine without error before.
Also, I cannot run Ocarina of Time Master Quest, it freezes on black screen once I choose the game. It launches fine, but freezes after the selection. Same applies for the 4 pack collectors edition, those games do not load for me. I made sure to keep them full size ISO, 1:1 MD5 verified with redump.