Open an old project, it takes a few for the wave forms to draw, then if I do an edit or zoom in and out they start re-drawing again....and again...and again....incredibly annoying And yes I have cleaned the pic cache folder. Am I doing something else wrong?
 
BTW this is on SPLAT.
 

im not sure whats going on to be honest. I would try 1st by updating your graphics drivers (onboard or not)
I just opened a Sonar X1 project last night and it was fine (no re draw issues at all.)
as a matter of fact I was a bit surprised the project opened flawlessly except is was missing 1 plug in.
(lexicon reverb that I no longer use).

Ha - funny you should mention that. I noticed the last couple of weeks that wave pictures are redrawing themselves and don't seem  to be stored and recalled instantly once saved as before. No idea why.