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I am having some difficulty identifying a problem on Nuendo. Under the "Performance Metre" on the top row of the tools, the metre is fluctuating up and down, going into the red. The system is lagging which may or may not be the result of this but when I put my cursor over the Performance Metre, it says "Disk Cache Overload". I have searched for a reason behind this and have failed to come up with anything. Can anyone shed any light on this situation.
and it was related to the videoplayback part. At the end it turned out the the harddisk was not fast enough to playback the video in that compression. I had to use a different video playback compression at that time.
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On windows look at the performance meters and resource monitor in system task manager (task manager, performance, resource monitor).
Is Nuendo only one app running? Try kill anything else and look what's happened to performance meter.
What's your setup (Hdd speed, ram, cpu etc.) anyway?
On mac you can do similar test.
As @gigicarlo mentioned maybe video can caused problems.