jdlk

Thank you for the detailed advice -- I'll work my way through the list. I'm using the most recent version of Avast (v7 home edition).

All requested log files attached in single zip file. logs1.zip

Okay. In support of my previous post, here are graphs of DPC latency on my system, with and without Malwarebytes' website blocking enabled: With web site blocking disabled: and with web site blocking enabled: The DPC latency spikes are always irregular.

After putting up with a long-term problem of stuttering sound when playing streamed audio, I finally got around to investigating the problem tonight. I noticed excessive DPC latency, and after a couple of hours fruitlessly disabling a bunch of drivers, I had a hunch and disabled Malwarebytes. DPC latency problem gone instantly. A quick Google lead me to this thread. As someone mentioned above, you can get around the problem by disabling malicious web site blocking, but that's hardly a solution. I joined the forums to take issue with the support response. Listening to streaming audio is not a marginal activity, and many people do it all the time when they're on their PCs (e.g. listening to internet radio stations). If you really can't solve this problem, then there should be a notice on your purchase page warning people that Malwarebytes can interfere with streaming audio or other real-time data streaming programs. My PC is a relatively modern Win7x64 machine.