Hi,
What could I possibly say? Reaktor 6's performance under macOS Sonoma on a brandnew Macbook Air M3 is downright abysmal. Worst performance of anything I used on that machine now. And fwiw: It performs quite a lot better (!) on my 2010 2x2.66GHz Mac Pro running Mojave.
In pretty much all typical DAW scenarios, the Macbook has around 3-4 times the singlethread juice of the Mac Pro, but with Reaktor I can not use Super 8, Form and some others at all, at least not at my audio settings (44.1kHz, 32 samples buffersize - and no, I'm not going to raise the latter at all, it's been one of the key reasons for me to buy the new Macbook).
Fwiw, Kontakt 7 Player performs lousily, too. Totally non fluid UI behaviour. Compared to Kontakt 6, it's pretty much shocking just how bad it is.
What gives?