(MBP) Cubase 7.5 \ 8 VST Performance Overload

I have a lot of spikes on cubase
i tried to reinstall and older versions
Its Impossible to work because it just spikes every few seconds

I have Macbook Pro Retina Mid 2012 15inch 8GB Ram 512SSD

what i need to do to fix that? :frowning:

other daw’s works perfect.