I am a noob with this stuff, but willing to try anything.
Let me explain the issue as clearly as possible.
On my cab, it seems as though the red is intermittent. The red will go out, and then randomly it will come back in.
I think it might be a loose wire somewhere, as if I am getting into a game a getting a little hard on my buttons or joysticks, the red will come back in sometimes. I have not hit my arcade machine (even though I have thought of it), but I am 99% sure that the red would temporarily come back if I did that.
What kind of stuff can I check?
The very first thing I did check was to ensure that the jamma board was securely in the jamma harness.
After I check what you suggest, if that does not help. what else can I check?