Wavelab Mac OS Pro Tools Hardware problem

Hi,
I would be happy to hear from anybody using Wavelab through a Avid Pro Tools HDX hardware.
My experience with Wavelab 9.5 (latest update) on a Mac Pro 6,1 (six Core) 2013 with the latest Pro Tools software (2019-12) and drivers has been disastrous.
With a master section loaded with plugins, everything grinds to a halt, wheel of death turning for ages etc.
What am I doing wrong ? is there some kind of asio driver I should download to interface with the Avid driver ?
I post this here on W10 because I am going to upgrade soon.
I have been a long time user of Wavelab on Windows (two computers, one for Pro Tools an one for Wavelab), but am thinking of going one computer only on Mac OS
Thanks
mark