Sounds play but the wrong ones.

The wrong sounds or tunes play

Cause: Sound board option switches, a stuck sound select line (S1, S2, S4, S8), or the sound, driver or control board.

Checks

• Check the sound board option switches.
• With a logic probe, check that the S1, S2, S4 and S8 select inputs to the sound board all pulse when sounds are called.

Fix

• A line that never pulses points to the driver board inverter or the control board; if all pulse, replace the sound board.

Systems

• Gottlieb System 80

Related tips

• No sound at all
• How the original System 80 sound board makes sound
• The original sound board self-test only works with S1 and S2 set opposite
• Supplies on the original System 80 sound board
• Sound command lines from the control board
• Original sound board option switches S1 and S2
• Fitting the original sound board PROM
• Fault-finding the original System 80 sound board

Source: System 80 Service Manual, Gottlieb