cable connector cleaner/contact enhancer

I spray deoxit D5 from time to time over the bare speaker wire ends on amp side and on speaker side.

Anyone use Kontak? 

I've gone through a couple bottles of Kontak over the years.  Like it, works great, but is just too expensive.  Caig DeOxit D5 cleans just as well at a fraction of the cost.  Alcohol can be used (although the D5 is far more effective), but stay away from rubbing alcohol which typically contains lanolin and/or other skin softeners that will leave a film.  Use a 95% or higher purity isopropyl alcohol instead.

bcowen, I agree with you on the rubbing alcohol. I mentioned "rubbing" alcohol previously but yes I too look or isopropyl or a high purity alcohol. Everclear is a pretty good choice :)
https://en.wikipedia.org/wiki/Everclear_(alcohol)

Use Kontak here. But my research led me to believe that the lack of residue, over time would be worth it.