Fun with Windows 7 CPU

Greetings all,
 
I could really use some of your expert brainstorming.  Several months ago I upgraded to Windows 7 Pro x64 (from XP x64), and performance in Sonar has suffered.  I have read countless threads and tried many things, but now it's reached a breaking point:  I cannot even playback most projects.
 
Symptoms
There is a constant crackle/popping/static during playback/record.  At times it gets so bad that the song even slows down in the sea of static.  Even with the ASIO buffer size cranked to the max (2,048 samples), there are still occasional pops (albeit MUCH less).
 
At the worst points during playback, the Windows Task Manager never reads above the 50%'s for SonarPDR.exe.  In Sonar, however, the CPU meter (bottom right taskbar) goes up to 100% + "Warning."  The large transport bar, which shows individual core activity, always shows the top core way higher than the others, and often maxed out.
 
I have contacted support at Cakewalk and Echo with no resolutions.  Cakewalk found no significance in the CPU discrepancy, and the rogue core in Sonar's display, but I feel something is going on there. 
 
Additional info
I have the onboard audio card disabled.  While Sonar is running, no other processes show activity besides "dwm.exe".  I did notice a process named "audiodg.exe" and two services, "AudioEndpointBuilder" and "AudioSrv" but killing/stopping them has no effect.  Oh, and switching off Aero did not help either.
Specs
XEON Dual Core 3ghz w/ Hyperthreading ON (it's even worse with HT off)
4 GB RAM
3 hard-drives w/ separate duties (OS, Audio, Samples)
Graphics card:  ATI FireGL 3400 (no Win 7 drivers available, using default drivers--could this be an issue?)
Sonar PE 8.5.3.282
I even upgraded my audio interface hoping that would resolve everything:
Echo Audiofire 8 (latest 5.5.6 driver; going to a TI chipset firewire card)
 
Plea for help
Thanks for reading (if you got this far). I'm happy to provide more details.  All positive suggestions are appreciated!

Thanks CJ, solid suggestions!  I forgot to mention:
1) I found no IRQ conflicts.
2) DPC latency checker stays under the green line, even at peak crackle!  (this is with HT on--crackle gets a lot worse with HT off)

WDM is a slight improvement, but still not usable.  Echo support told me to only use ASIO.

Nice ideas Tom.
 
Multiprocessing engine and MMCSS are both enabled.
No wireless adapter. 
Run as admin (interesting), disabling antivirus (Avast 5), and lowering UAC security had no effect.

Thank you though, very thoughtful suggestions!

My current firewire card has a TI chipset.  How would I be sure I'm upgrading?  Any specific brand/model?

What about upgrading to a newer graphics card?  Could my older ATI card be creating havoc since it's not using ATI drivers?

Any other ideas on the big CPU discrepency between Sonar and Windows Task Manager?

If a new graphics card got all running smoothly again I'd be ecstatic, so it's worth a shot.  I'm just trying not to sink more $$ into the computer (Dell Precision 490) if I truly need to upgrade the whole thing (a lot more $$$).

When I say a Vista/Windows 7 capable graphics card it does not need to be an expensive one. I paid $79 for mine. It works great.

Also try disabling Windows Core Parking ... http://forum.cakewalk.com/tm.aspx?m=1861804

Please list the total settings in options audio. There are 4 tabs the first 3 should be enough info. That is all your settings in those dialogs. I think something is set wrong or as CJ has said an IRQ conflict. This you can check in System Information.

DPC latency is OK right?

I looked at the thread and it maybe a driver/firmware issue. Can you test any other audio device? I suspect that its the driver or firmware.

Would you say that what they described there is what you get? If you can, try a version that is still 64 bits but is a much older version of the driver. This may mean you will need to reinstall Windows 7. Then load up the older driver. I would back up Windows 7 first.

I would try the on board sound chip if I had no other interface to test.

I want to add its been a pleasure posting to you. You understand things that others would need spelled out and you reply with cogent posts. For this and the fact that you are a forum member I truly hope you can get your system working. 

This may seem odd but I feel sad that it isn't working.

Thanks John!  I think you can see I do a lot of legwork before posting my woes.  But I don't want anybody to feel sad on my account

I was able to try the onboard sound (i.e. "High Definition Audio Device"), and get this:  same issue!  The static/crackle had a different timbre, but symptomatically the same.  This was with the Audiofire disabled and turned off.

I'm still baffled, but does this mean it's NOT an Echo, NOR firewire issue?  I don't want to dismiss anything entirely, as everything seems intertwined to some degree.  I hope this is finally narrowing down, but I'm unsure of the next steps. I already tried deleting the aud.ini.  Last ditch would be a clean reinstall of Windows, but that's a full day + affair.  And super-last-ditch is to purchase a new computer.

To get by for now, I've found the WDM drivers behave better than ASIO, although Echo support told me not to use anything but ASIO.  Can't listen to everybody eh?  Also, working in 64-bit Sonar adds another slight improvement in some cases, if I can work around the bit bridge issues.
 
P.S. Thank you A1MixMan, I had updated my BIOS to the latest available from Dell (which was May 2008), and installing a new graphics card + drivers didn't change anything.

My computer is 64-bit compatible, but thank you for your input.  All comments in this post have been so on-target and well-thought, thank you all!

I've gotten 3 BSOD's (blue screen's) over the last couple of days when powering on the Audiofire after booting/waking-up Windows.  I don't know how to read .dmp files, but the blue screens themself reveal echo1394.sys (the Echo driver) as the culprit.  I sent the dmp's to Echo, and hopefully we can resolve this.  I will surely post the findings!

More things to check...

- Disable everything in Control Panel / Sounds / Playback & Recording tabs.
- Disable Sonar / Options / Audio Options /  Share Drivers 1With Other Programs
- Disable Sonar / Options / Audio Options MMCSS (disabling this works at least with my RME Firefaces)
- List IRQs here for forum gurus
- Is Sonar in 48 kHz mode? Are you sure there's no sample rate mismatch?
- Bios: Plug'n'Play OS on/off if there is such option.
- Put Firewire card in another slot.
- Make sure Firewire cable is not bad (RME's advice for Fireface problems)

-Panu

+1 for Legacy driver.

If not using Legacy firewire driver I will get grief EVERY time. Without fail on an otherwise spanking quad core system... and I've built dozens over the journey. NO, I refuse to be labeled a geek alright.

Also, I do get a noticeably higher increase on my upper CPU bar too... never anything probelematic however and I've got one song up to 45 tracks with plenty of plugs etc.

Hope you get it sorted but I can only recommend the legacy driver very STRONGLY.

Cheers.

Seth Perlstein from Cakewalk made the suggestion of turning off core parking as this is know 5to be very bad for DAW's with multiple cores.

Did you try this because it looks as if his post was completely ignored?

Here's some info and how to turn it off

http://ultimatecomputers....pic.php?f=7&t=3644

And here..

http://forum.cakewalk.com...73&mpage=1#1852473

Maybe you've tried it already but I missed t somewhere but if not it's got to be cheaper than buying a new graphics card.
Oh, you already did.
Cheers
Steve