Drift mode enabled.
I just checked the system requirements on the Synthogy Ivory 3 page.
8-core 3.4GHz i7 (or AMD equivalent) recommended minimum.
3.4GHz? This will blow away almost any laptop. 3.4GHz is a desktop frequency. And here I thought of IK’s high demands…
Drift mode disabled.
Let’s talk about F278 again. I’ve noticed that on the IK forum almost all posts about Pianoverse have zero replies, or at most one. Not good.
So I don’t expect much help there. Some, like me, have contacted support and are still waiting for a response. I never had any luck with support other than Cantabile.
At least one good news.
This morning I did some work on F278. First I disabled everything, then added a few things one by one. Resonance, some mechanical noise, but no effects like compressor, rev, eq, piano ‘on Mars’, etc.
The quality of the samples still made for a great sound, helped by Fabfilter Pro R², which is very CPU light.
Result, with Buffer=256 I managed to stay around 25-40% TL. I haven’t tried 128 yet. I don’t dare. 
All this has reduced the artifacts, but don’t ask me why. There’s just some of the noise I mentioned before, but it’s reduced in level and doesn’t bother me much. And no more crackling.
After this fine tuning work, I’m very confident and the trigger is about to be pulled.