Check my post here (Official) Synthesizer V Studio 2 Post-Launch Follow-Up & Updates - #20 by Benefactor
It seems that Ableton is not the only factor, because it works fine on Ableton on another computer… yes, with more resources, but not much, and come on, I tested on a project with only one track (no other VSTs). Besides, resources should matter when rendering the vocal (and this works very fast even on a computer with less resources) and not when playing. The problem here is clearly with the interface…