Upgraded to Mac 12-core, have same ASIO/CPU in Cubase

I have a 12 core Mac Pro 5.1 with 32 gigs of ram, a pair of x5680 xeon processors, stock ATI Radeon HD 5770 1024 MB, SSD disks, Raid of 3x 3T, that makes 9 terabytes of 540Mb/sec. read/write huge sound library. My previous computer was an ordinary PC with K2700 I7 processor, 16 gigs of ram, running on Hackintosh Yosemite.
Cubase 10 Pro performed excellent on the old pc, but on the above mentioned Mac Pro with 12 cores and 24 threads, seems to use just one core! Whatever I do, I only get 115 % CPU usage on the latest Cubase 10.0.20 Pro.
On the latest logic Pro x, I get over 2300 %.
It runs at the full CPU usage and I can get about 300 tracks of virtual instruments.
The Cubase is simply impossible to use, because it is going at full processor use, on just few audio tracks,
Not to mention when I try to load VST instruments. A total disaster.
I tried with multiple audio interfaces, including the Mac’s sound card and never had a different results.
With each one of them, the Mac Pro performed almost the same, so the importance of audio interface considering this problem is not the case.
I tried other DAWs and the performance was always great.
Except cubase 10 Pro.
I am running a professional recording studio.
I use cubase from 1990 and it was my main DAW since 1997, when I switched from Digital tape recording (ADAT) to computer DAW, MacPro 9600, Mac G3 and all other Mac or hackintosh computers later.
What a disapointment.

Here are the benchmark results, so you can see that this Mac has excellent performance: