CakeAlexS
Maybe this will trigger something....
http://forums.guru3d.com/showthread.php?t=378151

It has!!! Success! ...er, sort of...
 
In the link, one poster speaks of PCIe v2.0. This piqued my interest as I wanted to see if the GTX670 was being bottle-necked somehow. Using an application called GPU-Z, I am able to view, in real-time, the operating stats of the GTX670 card. During idle times (e.g. Windows, browsing, etc.), the card is in PCI v1.1 mode, as reported by GPU-Z. To see if GTX670 would go into PCIe v2.0 mode, I booted a 3D game (Puddle) and ran it in a window. The result? The GTX670 did in fact kick into PCIe v2.0 mode, as reported by GPU-Z. So that's good!
 
Next, I shut down the game, and I fired up Sonar X2a and loaded my test project.  I pressed PLAY and checked GPU-Z.  GPU-Z reported PCIe v1.1 mode. However, upon mouse/MIDI-note movement, the card did kick into PCIe v2.0 mode. However, it was sporadic--sometimes it did, sometimes it didn't. And yes...Snap, Crackle and Pop were still present!
 
So next, I booted the game again, and ran it in a window, just as before.  With Sonar X2a still running, but not playing, GPU-Z reported the GTX670 was running (and maintaining) in PCIe v2.0 mode.  So for the final test I hit PLAY in Sonar X2a and moved the mouse around rapidly while holding a MIDI note in the PRV, the same as I always do. Guess what? No Snap, Crackle and Pop!!!
 
To confirm what I was [not] hearing, I loaded an instance of LatencyMon.exe, and checked the numbers.  Drivers were behaving themselves nicely! The worst offenders were again dxgkrnl.sys and nvlddmkm.sys...but their latencies both did not exceed 1.0ms! (0.999 and 0.748, respectively).
 
So what to do now? I will check my BIOS to see if I can always force "PCIe v2.0" mode. If not, then I'm not sure what my next steps might be.
 
However, here are some suggestion: Should future Sonar X_ versions be considered/programmed as a 3D application to fully utilize this hardware feature? Can Cakewalk provide a hotfix for us X2 users, and put a fix into X3d,e,f...z? (That would be nice). If it was confirmed by Cakewalk (by actually posting a bugfix list) that X3d utilized this hardware feature, then I would definitely upgrade.

2:43AM
 
So what to do now? I will check my BIOS to see if I can always force "PCIe v2.0" mode. If not, then I'm not sure what my next steps might be.
 

I'm sorry I can't help, but I appreciate your bringing this issue to light, and for the link to GPU-Z.  I didn't realize that my graphics card switched PCIe modes on demand.  Mine goes from PCIe1.1 to 3.0 and back.  Not a problem I imagine for graphics or playing games but might be with audio.  If I come across anything useful I'll post back.

Are you saying M-Audio MIDISport strains the CPU and cause crackles?  If so, I will unplug it.  1- I do more with virutal synths, and 2-There are tons of inexpensive MIDI interfaces.  I have an extra 2x2 sitting on my shelf and another 5x5 wouldn't be that big a deal.
 
Seriously need to know if this is an issue because I do hear crackle and digital distortion sometimes when every meter is green.  (By the way, I have the ASIO buffer on 1024.)

:) be interested to hear of the permanent solution, in the meantime playing Grand Theft Auto 5 whilst recording seems to be to solution! Take that you optimisation heads hahaha ;)
Nb nvidia control panel might do something for custom settings per app?

Back again with a little more information:
 
With the GTX670, when the computer is idle (or about 80% of the time when Sonar is playing audio), the graphics card is not only in PCIe v1.1 mode, but per GPU-Z, the GPU Core Clock rate is at 324MHz and the Memory Clock is at 162MHz.  However, when a 3D application is running, the GPU Core Clock ramps up and holds at 1019MHz and likewise the Memory Clock holds at 3GHz. It is when the card is in this "hi-speed" zone that no crackles occur. So it's important to point out that not only is the PCIe version (i.e. 1.1 or 2.0) important, but also the inherent speed that comes with it. This, in turn, has an effect on how an audio stream is handled.
 
Also note that Sonar may or not activate the "hi-speed" zone on the card. Sometimes it does, sometimes it doesn't. I notice that if I move MIDI notes around while holding the mouse for a long time, the card eventually kicks into high gear, and the crackles go away. It's only short-lived, however, and a few seconds later the card returns to slow speeds and the crackles come back.
 

konradh
Are you saying M-Audio MIDISport strains the CPU and cause crackles?  If so, I will unplug it.  1- I do more with virutal synths, and 2-There are tons of inexpensive MIDI interfaces.  I have an extra 2x2 sitting on my shelf and another 5x5 wouldn't be that big a deal.
 
Seriously need to know if this is an issue because I do hear crackle and digital distortion sometimes when every meter is green.  (By the way, I have the ASIO buffer on 1024.)

No the MIDISport does not strain the CPU and cause crackles. This is confirmed as I have tested and heard the crackles even when using no external hardware and triggering VSTi synths only. However, when the MIDISport is active, I have indeed observed a latency in the LatencyMon program, but I believe it's more of a latency created by the Nvidia drivers bogging down the system overall.  Therefore, all I/O data is affected by delayed IRQ's, timers, etc.  Shoot, the MIDIsports are one of the few products I believe in, going all the way back to my Mac days with the serial MIDIMacman! Those little metal boxes just work!

At this time I am looking within BIOS for anything I can do to force a particular PCIe mode. I will update again no matter what. Outlook not so good though...
 
But one simple question remains, perhaps to the Cakewalkers out there: why are the latencies almost non-existent, thereby causing very minimal crackles, if any, when the MultiDock is docked or resized to something other than fullscreen?
 
Afterall, this was the core question I started with. It just snowballed into this thread!

2:43AM
At this time I am looking within BIOS for anything I can do to force a particular PCIe mode. I will update again no matter what. Outlook not so good though...

You should be able to force your GPU to stay in high performance mode :
 
    "if you want a universal fix just go to NV Control panel and change the power management setting to "prefer maximum performance".
 
But I doubt this is a good idea as it will run hot.  There has to be something else going on.  For what it's worth I can't get X2a to kick my card out of PCIe 1.1 no matter what I do.
 

Here is a link for how to change the PCIe power setting.  No idea if it will solve your problem but its worth a shot.
 
http://www.sevenforums.co...-turn-off-windows.html

Anyone tried the usb hotfix?
 
Mine is off the scale but MS says no update required?

Paul P
You should be able to force your GPU to stay in high performance mode :
 
    "if you want a universal fix just go to NV Control panel and change the power management setting to "prefer maximum performance".
 
But I doubt this is a good idea as it will run hot.  There has to be something else going on.  For what it's worth I can't get X2a to kick my card out of PCIe 1.1 no matter what I do.

 
I have gone into the Nvidia control panel and turn Power Management Mode to "Prefer maximum performance," but it does not seem to have any bearing on PCIe mode or GPU clock speed, or at least from what I can see. Kind of a bummer so it seems to fall into one of those settings categories of "what exactly does it do then?" Maybe it's more for laptops and running on batteries?

lorneyb2
Here is a link for how to change the PCIe power setting.  No idea if it will solve your problem but its worth a shot.
http://www.sevenforums.co...-turn-off-windows.html

 
This was also done, but again, it seems to have no bearing on anything. Both this setting change, and the one above, did nothing to improve the crackling audio.

Jinxy
Anyone tried the usb hotfix?
Mine is off the scale but MS says no update required?

What's the USB hotfix? Link? This could be interesting to learn more since some of the USB IRQ's are shared with some of the PCIe bus IRQ's. My next couple of experiments is to move the mouse and keyboard around to different USB ports and try.
 
And in the BIOS for the ASUS P5Q mobo, I don't seem to have anything PCIe related, other than PCIE Frequency. This setting, however, can cause big problems if set to something other than 100MHz.