Issue: No background music. Fix: U42 (music control PIA) outputs test OK with Leon ROM but corrosion in area. Remove U41/42 PIAs, clean corrosion, and add sockets. No continuity from U42-16/17 to SRC3, fixed. Install new U41/42 PIAs. Remove U37 (LS138), clean corrosion, and add socket. Install new U37 chip.
Issue: Client reports game resetting. Bench test of drive board shows the following voltages, all of which are OK. TP1 = 12.6VDC TP2 = 5VDC TP3 = 12VDC TP8 = 19.3VDC Fix: Suspect bad grounding connection in game (screws, connectors, etc.) – replaced BR2, C5, and Q1 (with improved ground connection) anyways.