When you use MS Security Essentials together with uTorrent or other application which produces a high network traffic the DPC latency increases dramatically after 3-4 hours of working. If you restart uTorrent or disable and then re-enable the MSE Realtime
Protection the DPC latency drops back to minimal (normal) level.
Here are the screenshots (DPC Latency Checker from http://www.thesycon.de/ was used) :
1) The PC is restarted, MSE (with Realtime protection turned on) and uTorrent are loaded. The DPC Latency checker shows minimal DPC latency level: http://www.rugby-forum.ru/temp/morro1.jpg .
2) MSE and uTorrent were not restarted for 5-6 hours. Note the increased DPC Latency: http://www.rugby-forum.ru/temp/morro2.jpg .
3) The MSE Realtime protection was turned off and then back on. DPC latency drops back to minimal level: http://www.rugby-forum.ru/temp/morro3.jpg .
(Win7, latest MSE, Marvell Yukon 88E8055 PCI-E Gigabit Ethernet Controller with the latest Win7 drivers).
Last autumn I already reported this issue to the MSE developers during MSE beta program, but they marked this issue as 'not reproducible':
Product/Technology - Microsoft Security Essentials Beta
Feedback ID – 473290
Feedback Title – DPC Latency increases dramatically when using MSE with uTorrent
The following fields or values changed:
Field Status changed from [Active] to [Resolved]
Field Resolution changed from [None] to [Not Reproducible]
But the problem still persists, and there are many reports about this problem in Internet (for example: http://forum.utorrent.com/viewtopic.php?id=59644 ). Most of the users know nothing about DPC Latency, so they are reporting the issue as 'Music flickers/crackles when browsing the Internet','Sound output pops/crackles/hesitates', 'audio stops working after Windows 7 has been running for a while', 'Jerky sound playback Win7', 'Windows 7 Audio Stutter Problem' etc... This is because high DPC latency results in unstable audio playback.
Can we try to tackle this (rather important) issue down?