Yes I can reproduce it, but not at a specefic time.
When I am working in the solution, at one certain time, it appears, never on the same layout ar something. Just working in the solution, form layout to layout, from design to browse and vice-versa, and than after an halfhour it appears. I can send you the solution.
see the graphic, the processor is always jumping up and down.
I even tried to start with the StackTRACE=TRUE and than it happens too, after a certain of time.
No I never saw it in the client, but than again, I never work so offen in the client.