Love the game. Pulsed magna-saves and timed features make it great fun.
Just noticed you have a Firepower. That uses the same sound card + speech card as Jungle Lord (with different digitized speech of course).
Those rom sockets are famous for going bad. They should be replaced. The ribbon cable is not the 1st thing I'd look at.
Rom legs can be cleaned up a bit. Been using an art gum eraser, or sometimes a fiber glass sanding pen on legs. Can also re-tin them with solder and quickly wipe off the excess. They look like the rusty legs that tend to break off. There are people around here that can burn another set of roms for you, might have to search the threads. There is also a custom game rom set which adds skill shots and a "magna whirl" bagatelle random lane change (controlled by the magna-save buttons).
Pinwiki.com is my go-to site for repair tips, but I don't know how much they have on the sound boards. There have been other System 7 sound board repair threads, which might have good info.