Figured out my Marantz left channel crackle isn't due to the stereo relay, the problem is somewhere before the power amp, which narrows it down to...pretty much everything else (switchboards, tone control board, preamp, etc. It could be a bad capacitor, cold solder joint, or a faulty transistor. I guess all I can do is clean all the switches (for the umpteenth time), start switching out capacitors, and testing transistors. It's going to be a long road for sure, because the 2245 case is kind of stuffed, and a lot of boards have to be removed to see all of the boards under them. Sounds like that will be my winter-break project. I even checked to see if the screw under the tape relay was grounding it out, but it doesn't seem to be so simple an issue.
What are you guy's opinions of wiring up connectors to the wires on the boards, so they can be unplugged instead of needing to be desoldered for repair? More hassle than it's worth?