Analysis highlights/color spots in dirty shutdown occurs only under special circumstances, separate control shuts down or front panel key off is normal. Focus on checking the machine on/off switch machine control circuit. This machine adopts high standby, low level (or loss of) power control logic, so sharing CPU stopped working after shutdown, V576 cutoff, power control, capacitor discharge is granted. If, after the CPU stopped working, replaced by a switching power supply's output voltage-controlled V576, self-locking, will be able to solve the problem. Try CPU in the 7th foot take a 47k ω resistors to supply B5 (audio amp 25V), repeat the shutdown test, balls of light and "Ka" sound disappeared completely, and troubleshooting.