Sonar X3 / Focusrite Scarlett Solo - Issues with clicking on some VSTs (32bit?)

I've just bought a Focusrite Scarlett Solo, and testing it with my existing installation of Sonar. I've fully uninstalled ASIO4All (that I was using previously), but haven't yet tried a full Windows / Sonar reinstall.
 
Some VSTs have a rhythmic clicking on playback. Changing the buffer sizes only seems to change the speed of the clicking (and even at 1024 samples, I still hear clicks).
 
I can play the same VSTs outside of Cakewalk using SAVIHost (standalone VST host) and they play fine without any problems.
There are also a number of VSTs that do appear to play OK in Cakewalk.
 
It appears to be my older VSTs that have issues, so I'm wondering if it's a 32bit/64bit issue? I did install the x64 version of Sonar (it's a 64bit PC) - I haven't seen any issues previously when using ASIO4All (and a cheap Beranger interface).
However, the rgc Audio Square 1 is listed as '32bit' in description, but works OK - not sure why? (Full list of VSTs tested below).
I also tested live audio FX using a guitar and TH2 Producer - that also worked without issue.
 
Focusrite driver installed is 4.15.0.172
Sonar X3 version is X3e build 352 x64
PC Specs are  Core i7 4790S CPU @ 3.20 GHz 16GB RAM 64bit Windows 10 Pro
 
Does anyone have any ideas / suggestions / thoughts on this? I probably will do a full Windows reload in the next couple of weeks, but I'm not sure this will help in this instance?
 
Thanks very much,
Paul
 
 
All of the following VSTs appear to working OK:
Addictive Drums 2
Dimension Pro
Rapture
Session Drummer 3
sfz
SI Bass / Drums / Keys / Strings
rgc Audio Square 1  (Not sure why, as this is listed as 32 bit???)
Strum Acoustic
z3ta+
True Piano Cakewalk
TTS1
PSYN II
Roland GrooveSynth
 
TH2 Producer (Guitar FX for live audio input) also working fine
 
All of these plugins produce regular clicking when notes are played:
Cakewalk Sound Centre
DropZone
Korg WaveStation
Native Instruments B4
SampleTank

Yep, I've got a call logged with Focusrite as well....
However, the Focusrite ASIO drivers work fine with a standalone VST host, so I think it's a Sonar issue
I tried WASAPI drivers, but I couldn't get any sound out - however, I wasn't getting any signal from the audio track (despite having signal on the midi track, and that output going to the audio track). I'll try again a bit later......
 
Thanks for your suggestions...

You should be getting better performance with ASIO than that.  A few things to try /look at:
 
- Make sure you have the proper generation (1st or 2nd) drivers for your Solo.
 
- Connect the Solo only to a USB2 port (not USB3).  Or, try a different USB2 port.
 
- Did you do a reset & rescan of VSTs?

A USB3 port with Intel controller/driver "might" work.  A look at the device manager will tell you if you have any.
 
An added hub won't make a difference if it's connected to a USB3 port.
 
If this is a desktop, there's another, easier solution. You can buy a relatively cheap USB2 PCIe add-on card like this one:
 
https://www.amazon.com/Syba-Expres-5-port-Host-Controller/dp/B0026I4DZ2

A long-shot, but worth a try...
 
Under Pref/Audio/Driver settings:  Disable 64-bit Double Precision Engine (Has been known to cause problems with some plugins).

I would file a problem report with Cakewalk if you haven't already.
 
https://www.cakewalk.com/Support/Contact/Problem-Report
 
I would also experiment more with WASAPI and WASAPI Exclusive in the meantime. Windows Audio has been improved in recent months and Sonar has been optimized for it (nevermind, I see you're on X3).
 
I haven't tried any alternatives to jBridge / BitBridge because I (luckily) haven't needed to.
 
EDIT: You might even want to try your integrated audio as a temporary work around.

Thanks Marled -Although I'm sorry to hear you're having problems, I am pleased to hear the problems exist on another setup.
I have a call open with Focusrite about this, but their response so far has been similarly 'generic'....

Hi,
Focusrite support have confirmed this as a bug:
 
 
 
Hi Paul,

Thanks for your reply,

Apologies for the delay in response. I've managed to test this with Sonar and I have managed to reproduce the problems you are having on 4.15 with Sonar.

I'll log this as a bug case and add you to the case.

During initial testing I could not reproduce this on the 4.14 driver so I would recommend installing this and let me know how this goes. 

I've also CC'd myself to this thread so I'll be notified when you reply.
Best Regards,
Ed Fry
Focusrite Technical Support

Just wondering if the Splat 2017.01 update might of addressed this. I will have to try on my set up later.
 

Using 4.15 but I am a hoarder and kept the 4.14 driver so might try rolling back when I'm not too busy . Then again I think as Focusrite are on the case, wait for the next driver.