It is my computer at work, I have disabled  the screen saver, as I am working from home. so, it works well now. 

Actually, it is like NVDA is on speed. 

To keep NVDA functioning over the last few weeks I tweaked every setting I could only found that the screen saver was processing data last Friday. so now with the screen saver disabled, and all the other tweaks NVDA runs very well.