[gunhijala]

If it only happens on those type of shot's I'd say it's a weight transfer thing. (and no, that was not a comment on your weight, lol). I have it fairly often because of leg and circulation problems in my legs. If I stay down well on the shot I sometimes seem to put too much weight on my toes if the ball is above my feet.

I agree, but no clue how to fix it. I first have to figure out what I'm doing wrong.