Artifacts/dropouts Win7/console/sir1 setup Help?

[JonHag]

Hi
I am very sorry if my issue has been discussed else where. I couldn't find an answer by searching.

My problem is that while playing back audio, there is sometimes small disturbances in the sound. Like very short pauses.

My setup:
PC with win7 (also had the problem with XP)
Console VST-host running asio
SIR1 VST convolver (fir filter 1000 taps) 4 instances
Mediaplayer (problem also existent with foobar)

My setup is 2-channel, so i am doing convolution on 2xtweeter and 2xwoofer.
Sound card is lynx-twoB. I use a jumper to route back pc-application audio to the lynx-mixer in order to pass all audio thru console.
In console there is a CPU load indicator wich usually reads a total of ~3% but sometimes it jumps to 50-100%. This is sometimes, but not always, related to the sound disturbances. These CPU-jumps are not seen on windows task-manager performance monitor!?! I guess this is averaged for a longer period of time.
The problem happens both when playing back music from the HD, and from the cd-rom drive, but i am not sure if it happens of equal frequency.

So, any idear of where to look?

And thanks very much in advance for your time.

Regards, Jon.

[1audio]

You are probably running into internal underruns, i.e. the system running out of data. If the system isn't carefully optimized any of a number of background tasks can suddenly bump the audio thread. And the filters you are using may also have some periodic demands that don't show. Sysinternals has a more comprehensive toolset for looking at internal loads.

[wwenze]

You might want to use task manager to see which program is causing the CPU load

Also you can try this:

DPC Latency Checker

[phofman]

In case you do not need to keep latency low, you can raise ASIO buffers to give your system more time headroom.