I have a Robo-War, which is awesome! Even more exciting, it is out of my friend's place, and back in mine, so I can work on it.
The sound--it plays music, but no sound effects. However, just a half an hour ago, there were a few laser and explosion sound effects which were very quiet, but audible. I poked at the little potentiometer(?) on the mini-board with the power transistor attatched to a large heat sink above the sound board, and the game re-started. No more sound effects. But, could this indicate something I could replace?
I am not saavy with chip replacement, but could replace anything else on the boards.
Thoughts, anyone?

Gotcha.
Noob schooled.
I'll pull out the multi-meter.
Thank you.

Any other advice about sound?

Sorry, Chris. I do not have adequate means for the posting of a video, or taking of one, really. It's got the 80B sound board, and has seen nothing but home use for the past 10 years. However, I believe the previous owner (I bought it almost two years ago) did not remember any voice or sound effects.
I am having some work done to the Black Knight, which is on location, so I moved it to the location. The electrical connector clips look like they could stand replacement on the speakers, as there was a little crackling coming from the upper speakers. Every few games, those feature sound effects seem to come back very faintly, but no voice. Would anyone be willing to service it for me, if I mailed the proper boards?