What contact cleaner do you recommend?

The one issue for ALL the products is to use a very tiny amount. More is NOT better with a contact enhancer.

So the point is put the fluid on the surface, then wipe the surface off. Not squeeky clean, but pretty dry. One only wants a few molecule thick layer on the stuff on the surface. If you can see or touch it and get some on your finger, you left TOO MUCH on the surface.

That advice applies to all the products. Tweek, Caig, and the silver stuff.

Good advice Elizabeth. I too use Caig very lightly about only once year but am happy with the results. Also use it on my guitar amps, pots and connections too.

Tweek. Excellent example of a contact enhancer that does degrade over time. It turns a dark greenish black. By contrast, Cramolin Red, the one used in aircraft communications electronics, works great and does not degrade over time.

i just thought of another solvent that could be considered,namely, cramolin.

Mrtennis - Pretty sure you just experienced Morphic Resonance. :-)