Is the LED on the soundboard blinking after the game is powered on? This soundboard has 2 sections, 1 taking care for background sound and the other for sound effects. It seems one section is not starting. Maybe you have bad luck and an Eprom or memory chip died at the soundboard. You can try to adjust the +5V with a multimeter. Another thing you can try is cleaning the edge connectors (aka cardboardconnectors) from the driver and CPU board. Use a fiberglass pencil or just an eraser. Notice it is not a Groundproblem....otherwise the other section would have been dead too.
Btw.....Night Moves......looking for it for years.....
Good luck!
Marco