MBP freezing while using external monitor?

I've done searches but I haven't been able to come up with anything concrete.

My MBP keeps freezing while in clamshell mode, hooked up to an external monitor. Everything will appear to be normal, but I'll do something as simple as open Safari or even bring up the dashboard and the the image freezes. Anything in the background (music, video etc.) continues to run as I can hear it, but graphically nothing happens. I'm forced to hard-reset the machine and try again. There doesn't seem to be anything I'm doing in particular for it to happen and it doesn't happen when using the internal LCD.

Any ideas of what this may be and if I ought to talk to Apple about it? Thanks!

-M

Have you tried another monitor to see if the same thing happens? The freezing may have something to do with your MBP graphic adaptor settings. Check all your display settings, try another cable. For example: If the monitor is hooked up via DVI, try using VGA or vice - versa. Also make sure your MBP is set to the native resolution of the external monitor.

Regards.