Me too. I have a VERY heavy touch and I clank a lot on fretted basses - fortunately I only use these for rock and metal playing, and it's reduced on my fretless cos it doesn't have, erm, frets.
It's like slapping; you'll be conscious of trying to master the technique and getting a lovely bouncy, fluent feel to your lines and it'll really get you down for a while. Then one day it'll just 'click'.
Days like that are just awesome, so keep going!