I'm editing a large project; running 9C in Win7/64 with 8GB RAM. Vegas performs admirably and I've rarely had a crash despite the size of the project. However, if I switch to another program, such as Windows Explorer, when I return to Vegas I have to wait for a minute or more for Vegas to 'revive." Is this normal? Any way to correct/avoid this other than not running multiple programs at once, which is not always an option?

I was noticing the same thing until -

Go to Options > Preferences > General : "Untick" - Close media files when not the active application.

Seems to have helped me.

Note that you will not be able to edit files in another program and then save them and have them automatically update after that setting is changed. Sometimes that's fine. Sometimes it is not.

Thanks Jim and Edward, that works. It was simply an annoyance, that has now been resolved.