When using the touchpad, if I do a right click gesture (touch with another finger), the cursor often jumps vertically. This has the unfortunate effect that the right click event may no longer be on the object I wanted to click (eg: a hyperlink).
Playing with it a little, it seems to jump vertically if I tap slightly off the horizontal line from the finger already on the touchpad - as if the vertical cursor position is an average of the two finger positions.
I can also achieve a horizontal jump if I tap just off the vertical line from the finger already on the pad.
If I tap at about 45 degrees, the cursor is pretty stable. It appears to be in an approximately 5mm strip either side of horizontal/vertical that the problem occurs.