Here is a video (no sound) of Kevin cleaning an ARP Odyssey (these were manufactured from 1972 through 1981):
Look at the volume of crud coming off the boards. The key is soft fresh water, no soap and forced air drying immediately after. Too many technicians just squirt some "lube" into the connections and that will fix it for a while but the lube only serves to hold more dist and grit and causes failure to happen soon. From Kevin:
This is how we clean most synths during restoration. Unlike many approaches at slider "cleaning", we feel the dirt should actually be removed and not just some solvent sprayed in. Note that this is how WE clean things, but not necessarily a recommendation for everyone. Soft water is used and these parts are blown dry with compressed air immediately afterward. No opportunity is allowed for oxidation. We have cleaned most synths this exact way for over 15 years. Done correctly, it causes no problems.
He will be missed...