1 Topic by Har (edited by Har 2011-05-12 10:13:23)

  • Har
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Topic: Out of control CPU usage

I'm having a strange issue with my Babyface that's crippling my ASIO performance. Upon starting Windows, usually one CPU core is jumping between 20 to 40% usage in a semi-regular cycle, and if I open an audio application it starts jumping between 0 and 100% until I close the program. Checking resource monitor shows it's originating from system interrupts (deferred procedure calls/interrupt service routines). After unplugging the USB cable from the Babyface, the CPU usage disappears, and once I plug it back in, everything is normal until the next time I restart.

http://i.imgur.com/VBXS3.jpg

I'm on Win7 x64, driver version makes no real difference (affecting the cpu usage slightly but not the general behaviour). Power saving features are disabled though core parking is still enabled; I'd prefer not doing registry tweaks if possible. Also I only noticed this a day or two ago and I've had the unit for about 2 weeks, but I can't think of anything major that would have affected USB performance.

  • Registered: 2008-01-01
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Re: Out of control CPU usage

What sample buffer size do you use when this happens?

  • Har
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Re: Out of control CPU usage

It happens regardless of the buffer size and sample rate unfortunately.

  • Registered: 2008-01-01
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Re: Out of control CPU usage

Are you sure that you are not using multiples of 48 samples as buffer-size when this happens (48/96/192)?

Make sure to use W7 Service Pack 1 and set the power-scheme to "High Performance".

  • Har
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Re: Out of control CPU usage

Just tried it with all buffer settings available, no help. Also I've had SP1 for a while and I'm running the high performance profile with everything tweaked to remove power saving features.

6 Reply by Har (edited by Har 2011-05-12 22:35:42)

  • Har
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Re: Out of control CPU usage

I've tried everything I can think of including reverting Windows updates, disabling and removing unnecessary devices, removing old drivers that were left over, a Microsoft hotfix that said it wasn't applicable to my system, moving the unit to a different USB port, disabling all USB power management, and uninstalling the USB controllers themselves to allow them to reinstall. Still this odd problem persists until I disconnect and reconnect it from the port. It also rarely works without the issue straight from bootup, maybe 1/10 times.

  • mse
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Re: Out of control CPU usage

Just exact like my problem.

And my problem is on the forum: http://www.rme-audio.de/forum/viewtopic.php?id=11077

8 Reply by Har (edited by Har 2011-05-13 01:55:00)

  • Har
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Re: Out of control CPU usage

mse wrote:

Just exact like my problem.

And my problem is on the forum: http://www.rme-audio.de/forum/viewtopic.php?id=11077

Yep, sounds like my problem, only I just tried shutting down instead of restarting and the problem still happens. What kind of hardware do you have?

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Re: Out of control CPU usage

Mainboard: MSI K8N SLI-FI
CPU: AMD 3800+
GPU: NVidia 8800 GT
RAM: 2 GB
OS: Windows 7 Ultimate x64 SP1

Babyface: Driver version 0.979,
Hardware revision 179, TmFx version 0.93

10 Reply by Har

  • Har
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Re: Out of control CPU usage

Hmm, so same issue on an Intel chipset and an AMD chipset... I guess the OS or some software is to blame then. Any ideas from the RME staff?