[2005] VB Missing MouseMove event

I have a PictureBox with labels on it. The labels can be "dragged" across the pictureBox by handling the mousedown, mousemove, and mouseup events of the label, but for whatever reason, they have stopped responding to any mousemove events that are outside the bounds of the label. So if I move the mouse very slowly, the label follows that movement as expected, but if I move the mouse fast, such that the first mousemove event is outside the bounds of the label, no mouseMove event fires for that label. Instead I get a mousemove event for the PictureBox. The weird thing is this has always worked for me with labels until now and still works correctly for panels on same PictureBox that point to the SAME eventHandler. Has anyone seen this problem or any ideas on what is going on? If you need to see some code, lmk...

Thanx.

I think you'll need to post the relevant code...