Has anyone noticed the channel editor stop responding to the mouse when editing key frames? I've noticed that it starts fine, but over time it eventually stops responding the mouse with the exception of being able to select the key frame. At this point it won't let you drag the key frame or change the control points for the curve. You can edit the value, Slope, and Accel manually in the edit boxes, but that's kind of a drag. The only thing that gets this working again is to restart H. Is there any other workaround? Any idea what might cause this? I'm using a character that I built that's a DA, with around 400 channels total. The animation itself is about 270 frames.

This is on H 12.5.615, 64 bit, Windows 7 64 bit, Nvidia Quadro 4000 with driver 331.82, 2048MB VRAM.