Cubase 11.0.2 on Big Sur Macbook pro 16'' unusable with CPU Spikes

Hi Everyone, I’m having an insane amount of problems with Cubase since I did updates, today I tried to open a project I finished couple of months ago for an Advert, with the same Buffer size settings (1024) and also wibnt 2048 buffer the Cpu meter is always at 100% and Cubase in Activity monitor is using 300% of CPU, I also have similar problem ith newer projects with 6 or 7 audio tracks. I don’t understand why is doing this, I tried with other DAW and i can work without prioblems, I’ve also reset all Cubase preferences in safe mode, still no luck. Do you have any solutions? suggestions?
I bought cubase in december thinking that was the best DAW out there, but I think I’ll go back to Ableton Soon cause is impossibile to have all these problems.

Also I have to Add that the CPU Overload is not immediate, if I play the project it starts ok then after 2 or 3 time i press play th Average goes at 100% and stay there even if the project not playing, if I freeze stuff nothing will change after