this is a problem with burnt resistors on the mobo ... one of them has a short circuit to the next one (they're packs of 8 resistors in the same part, close to the bios chip) When the PS2 crashes they can overheat due to bus contention and this might cause the PS2 to stop working totally or have the "Gold disc" problem, which seem to be your case.
SCPH-10000_GH-001 SCPH-15000_GH-003 SCPH-18000_GH-008 SCPH-30001_GH-005 SCPH-30000_GH-016(V4) SCPH-30001_GH-010(V4)
2xSCPH-10190, 2xSCPH-10350, 2xSCPH-10280
"**** j0 hackers!"
-Sjeep (As seen on TOXIC OS ELF...)