How To Reduce Float On Spd Pedal

I've been using the shimano M520 mtb spd pedals with specialized mtb shoes. I have no problem clipping in and out, but what annoys me is the float movement of the shoes, specially the right one.
My left foot is locked with almost no float, keeping the ankle straight, which is great (no pain or discomfort) but the right foot tends to rotate (something to do with my natural foot alignment, toe-in) I try to keep it straight however I find myself turning the pedals with my ankle pointing out and that causes a bit of discomfort. It stops after I straight it back and ride for a few minutes.
What I'd like to achieve is to set the rotational range. I know pretty much the best position for my cleat and shoe.. I just need to find a way of keeping it in that position.
Is there a way to reduce float on an SPD pedal, through adjustment or cleat type?
My left foot is locked with almost no float, keeping the ankle straight, which is great (no pain or discomfort) but the right foot tends to rotate (something to do with my natural foot alignment, toe-in) I try to keep it straight however I find myself turning the pedals with my ankle pointing out and that causes a bit of discomfort. It stops after I straight it back and ride for a few minutes.
What I'd like to achieve is to set the rotational range. I know pretty much the best position for my cleat and shoe.. I just need to find a way of keeping it in that position.
Is there a way to reduce float on an SPD pedal, through adjustment or cleat type?

Mar 21, 2010 Symptom- One of the pedals didn't engage as well as the other and was very tight feeling with respect to the float. The 'good' pedal/shoe made a nice click when engaging and had easy float. The 'bad' pedal/shoe made a dull thunk when engaging and the float. Studio manager v2 host and editor.