Metro Heights performance issues

I’m having hard times to get Metro Heights to work under GA4. Even the most “simple” patterns will lead to CPU spikes unless I increase the ASIO buffer to at least 256 samples running @44.1kHz. And this is only true for an empty project in Nuendo. On average project load, Metro Heights cannot be used at all.
Limiting the voices to below ~128 does help of course, but decreases the sound quality a lot.

Is there anything that I’m missing out? Or is this drumset made for computers that do not exist yet?

Installing GA5 as a trial version removes all issues. It runs smoothly, whereas GA4 is still virtually unusable with Metro Heights and most other high quality drums sets. I hope the upgrade from Absolute 3 to Absolute 4 will come soon - before my trial expires. If not, I think I will make a claim, this time.