mad involuntary canvas panning

Hi David,

I am experiencing an insanely annoying canvas behaviour:

from time to time (I can't really say what's triggering it, unfortunately...) the canvas focus moves "on it's own" everytime I press a mouse button.

If I try to pan (right click) the canvas pans out in a flash to some place in the far northwest.

If I select and try to move any component (left click) the movement also appears, and the component gets dragged along with it.

This is persistent (closing the gh file and opening another doesn't help), the only way I can deal with it is by relaunching Rhino.

I've attached a short screengrab, in the video first I try panning then dragging a component by a small amount. The last bit shows that if I move quickly enough (!) I can manage to avoid the automatic panning. (This is of course an act of pure despair...)

I'm running:

Vista x64 / Rhino 4.0 SR9 / GH 0.8.0066

Thanks in advance for any info on this issue,

Regards,

Jacek