CPU Crackling and Popping Issue

[jimbo68]

Howdy.  Glad to join you all.   I have just gotten into picking up mostly 70s and 80s arcade games.  One such is a Tandy 51 game upright arcade cabinet style game that is a project.  I have plugged it in a couple of times and there were some issues with interfacing in the game selection screen.  At times I could not select the game I wanted to play.   However, today, I plugged it in and heard a crackling sound and then nothing came on.  I unplugged, disengaged the CPU harness, turned it back on and no crackling sound.   I reengaged the harness, re-started the game and got the crackling and popping sound and no game again. 

The game is out in the carport right now while I paint the cabinet.  It is in the 60s and drizzly, so it is humid.  Could this be the issue?

Would love to get some insight, as I really don't want to ruin this project game.  I certainly will be happy to answer questions or even try to post a video if needed.

Thanks,

Jim