I got a same problem here. Sonar Pt x64 kingston, Windows 10 (64bit), Ivory II 2.1.2(updated), 
If 64bit Engine is checked, there is a huge distortion with ivory II
(in Sonar x3 32bit, it was fine whether 64bit engine is checked or not)
 
I think  this is a bug or some kind of software crash of Sonar pt.

Here's hoping a fix is to come soon (even though turning off 64bit engine seems to be of no seriously negative consequence).

FWIW, I've got the issue as well (and as far as I know, only with Ivory II). DPE does not seem to matter, the distortion is there regardless of whether it's checked/unchecked (though I have not yet created a new project from scratch with the DPE off). I hadn't noted it earlier as I've been working mainly with more guitar-based projects (i.e., no piano).
 
It's extremely disconcerting. I don't think I'll ever get used to that sound. It might as well be fingernails across a chalkboard for me. 

outland144k
FWIW, I've got the issue as well (and as far as I know, only with Ivory II). DPE does not seem to matter, the distortion is there regardless of whether it's checked/unchecked. 

Not the case here. Probably something about our respective setups.
 
I can stop an existing project from getting that sound by turning off DPE.

I guess I'll roll back to Jamaica Plains (at least when I start a project in which I need Ivory II).  I'm hoping that a fix comes out before I do that obviously.
 
What is also strange is that Cantabile is distorted after attempting to run the Ivory Vst in Sonar.  It's a different type of distortion, not as strident. It is also easily fixed by opening the RME driver and resetting the sample rate (even setting it to the same sample rate works fine).  I wish fixing the Vst were as simple.

I should attempt the order Jackson used above.  I'll do that tonight.

A few questions for you all:
 
Is it better to roll back to Jamaica Plains or proceed with the Double Precision Engine turned off?
 
Are bears Catholic?
 
Does the Pope live in the woods?
 
How much wood would a woodchuck chuck if a woodchuck would just cross the road, for Pete's sake?
 
 

Hi Dan,
 
We're rolling out a fix for this today. If you're still experiencing the trouble after the update please let me know with a PM.
 
Thanks,
Daniel [Cakewalk]

An update to address the double precision issue should be available today.
Keith

Dan Cate [Cakewalk]
Hi Dan,
 
We're rolling out a fix for this today. If you're still experiencing the trouble after the update please let me know with a PM.
 
Thanks,
Daniel [Cakewalk]

Keith Albright [Cakewalk]
An update to address the double precision issue should be available today.
Keith

 
Thanks, guys, much appreciated. Will this be handled with Command Center? (Pretty much everything is handled through Command Center, right?)



The answer to that pesky "airspeed velocity of an unladen swallow ("african or european?")" question:
 
http://style.org/unladenswallow/