What’s your favorite cleaning method for connections

Deoxit is great.

A good substitute is Isopropyl Alcohol, readily available at pharmacies.

I also use a scouring pad (not steel wool) to remove oxidation (tarnishing), especially from silver connections.

A very simple thing to do is to simply rotate the jack in its plug back and forth a few times, although this technique is not as reliable as the others mentioned.

Balanced connections are a bit more difficult, but the above methods are still effective,

Electroscope looks a lot like crc to me which I have been using. They make one for electronics that is plastic safe. Haven’t tried deoxit yet but I’ll check it out. My repair guy uses the one that has lubricants in it for switches. Maybe there’s one for contact points too 

Deficit

Isopropanol.

Cheap, mildly toxic rocket fuel. I have used everything over time and this works the best. Drop some onto toilet paper, clean and then breath on and dry with another wedge of the same. Do not use with wet fingers.

Clean well with deoxIT then spray on preservIT. Pretty much the industry standard for recording studios & audio gear. Supposedly cleans & improves conductivity. I use it on my tube pins as well.