After working in the sheet tabs (arranging layouts, adding text to sheets, selecting layer visibility in viewports etc) the model space becomes very slow and unresponsive. Even in very large drawings, the model space is absolutely fine, quick and active, until I start doing some work in the sheet tabs, and only then does the problem start.

Has anyone else been having this problem? Any ideas on a solution? (I'm running SP2 on a 64bit machine with ample power for 2D CAD drafting).

Cheers, Ed.