Cubase super slow working with Vienna Ensemble Pro


I’m having a lot of issues with Cubase 10.5 and Vienna Ensemble Pro, and I wish I could find out if it’s in relation with the softwares or with my computer?

First, I’m working on an iMac Retina 5K - 27 inches, late 2015. Processor is 4 GHz Intel Core i7, Ram is 32 GO. Using a RME Fireface 802.

I’m not used to make big templates, but I’m about having to deal with orchestra and I started with a template under Vienna Ensemble Pro composed with 3 instances of 4-5 instruments each, so we’re in a total of 15 instruments more or less, which doesn’t seem so big… I mean I may have to work with even more instruments in the future.

When I open my project, it sort of works ok at the beginning, but very soon Cubase can"t stop autosaving the project (and Vienna serveur instance at the same time), which makes it almost impossible to work. The little round is turning and I just have to wait. It usually comes back each time I move the mouse or touch something with it on the project window.

It seems like it takes all the Ram memory too - I have Cleanmymac installed and regularly I have to free the memory, which goes so low as 29 Mo… And the CPU load goes to 20 pour-cent.

Does anyone know if this is a computer problem or a software problem (from VSL or Cubase)?

Thanks as lot,