PROBLEM SOLVED!!!
I managed to fix the problem (well at least get rid of it on this computer).
I started going through the different scenrios and decided that the only possibly explanation is an incompatibility between teh charting control and the video driver. I reduced the Hardware acceleration of the video card just one notch and the problem went away. I then downloaded the latest version of the video driver (ATI RADEON 7000), installed it, bumped the hardware acceleration back up to full and the problem is gone!
There is obviously an incompatibility issue there.
