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I've got an XP SP3 machine with an odd problem when coming out of standby sometimes. After starting back up the machine will rhythmically stutter at a fixed interval with one of my four cores pegged at 100% during this time. Also, if my speakers are on, I will hear a high frequency hum during the stuttering.

A look at Task Manager shows no tasks taking any CPU time, but it does report 25% Kernel Time during the stuttering. A look at Process Explorer shows no tasks taking CPU, except Hardware Interrupts are the culprit during the stuttering.

Machine was last known not to do this about 2 months ago before I moved. Since then there have been a few driver updates and patches installed. I recently installed a Wacom Bamboo Tablet, however, uninstalling this device and driver did not change anything. I've also uninstalled and updated my sound card drivers, which also did not change anything.

I've exhausted my sysinternals-fu and cannot figure out how to determine which of my hardware devices is the problem child. Where should I go next?

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up vote 2 down vote accepted

As suggested by @Shinrai, I worked down the list of devices and drivers including rolling back such things as chipset drivers. Unfortunately these attempts did not change anything. A cursory look through device manager revealed nothing as well.

However, when I took a look at Event Viewer it became obvious who the culprit was! 1500+ entries for a CDROM failure

Almost every second there was a failure from \Device\cdrom0:

Event Type: Error
Event Source: Cdrom
Event Category: None
Event ID: 15
The device, \Device\CdRom0, is not ready for access yet.

At this point I opened up the properties for the device, but everything seemed in order. However, the rhythmic high pitched hum I was hearing through my speakers prompted me to disable the Digital Audio input.

Unchecked digital audio input

Viola, no more stuttering or digital humming! Now just to figure out why the CDROM fails coming out of standby...

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I have no input on the problem with the CD because I've never seen this behavior. What's the manufacture of the drive? – Shinrai Jun 9 '11 at 4:20
@Shinrai: it is a LiteOn DVDRW drive, but now it displays as "ZBA8472 CED34892 DVD+RW", which seems odd. I don't actually recall what it used to say, but certainly not that. I'm going to unplug/replug it in when I get home today; maybe that will fix it :) – user7116 Jun 9 '11 at 14:09
Did that fix it? – Shinrai Jun 10 '11 at 22:57
@Shinrai: Nope wasn't a loose connection. It still has the messed up device name. How very odd. But the definite cause is the digital audio being enabled coming out of standby. – user7116 Jun 10 '11 at 23:25
Weiiiird. I've never seen behavior like that. – Shinrai Jun 12 '11 at 3:45

Even just reading the title I suspected a bad hardware driver, before I got to reading about your checks. :) It's entirely possible that an unrelated update is interfering with a previously installed driver, or even that you have a device that's actually got something wrong with it.

The tedious, but probably foolproof thing to do is to manually uninstall each and every device in the machine one at a time until the behavior stops, and there's (at least a big hint towards) your culprit.

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I've uninstalled each device I considered a possible culprit, rolled back video drivers as well. My main rub is this doesn't always happen when I come out of sleep, which makes determining if I've fixed it really obnoxious. – user7116 Jun 8 '11 at 16:08
It could very well be a chipset driver or something more integral than you think. EVERYTHING is a possible culprit, I'm afraid. – Shinrai Jun 8 '11 at 16:27
Fair enough, we'll see if rolling back the chipset drivers fixed it. Gotta wait till I get home and take it out of standby. – user7116 Jun 8 '11 at 16:29
@Shinrai: see my answer as to which one was the culprit. – user7116 Jun 9 '11 at 1:47
@sixlettervariables - Aha! (For the record, I didn't think it was likely to be the chipset driver, that was just the first example of something you wouldn't normally suspect that came to mind.) I'm glad you managed to figure it out without having to drill too deeply! – Shinrai Jun 9 '11 at 3:09

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