I found this on Atari Age, so I take no credit for myself. But I tried it last night and it worked perfectly.
At Radio Shack, for $9.99 CAD, I bought a can of Tuner Cleaner (I think that's what the label said). AA said to use Cleaner/Degreaser, but this was the closest thing my RS had (it said Cleaner/Lubricator, so I figured how can I go wrong).
I took the back off of my Paddles and sprayed it into the paddle itself (after moving the button out of the way and ensuring I didn't get any on the rest of the paddle). Put it back in and tried it with Kaboom (Atari 400 version).
Worked like a *charm* I don't think I've *ever* had a paddle so responsive before. No more jumping around! Now I can go back to playing some recent VCS Paddle purchases like Circus Atari, Breakout, and Demons to Diamonds!