Solved Surface Book (Maybe SP4) camera drivers (Intel AVStream) causing insanely high DPC latency!

[Vbman213]

Noticed some audio distortion when my camera was enabled.

Installed LatencyMon to measure DPC latency.

Here are my results:

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The first two images are taken with the camera disabled/off

The last two images are taken with the camera enabled/on

 

[GreyFox7]

Which Camera? Infrared or Regular? do you have Windows Hello on?

 

[Vbman213]

Regular camera, front or back.

I performed this test using the built in camera app

Edit: I tested with Windows Hello on and off. Same results. Same latency

 

[GreyFox7]

I guess this is what we should expect from the Fail Forward Fast era mentality... a lot of mistakes.

 

[Vbman213]

After patching today, I can confirm that this problem is gone on my unit. My DPC latency is now MUCH improved. Check this out:

Imgur: The most awesome images on the Internet