# feedback through speakers when scrolling



## decuser (Aug 31, 2017)

This is interesting, but annoying. Anytime I scroll in a browser window, or even just click and hold the scrollbar, I get a faint humming through my speakers. Has anyone else experienced this and does anyone have any idea how to fix it?

My relevant specs are:
Dell Optiplex 755

```
Intel(R) Core(TM)2 Quad  CPU   Q9550  @ 2.83GHz
pcm0: <Analog Devices AD1984 (Analog)> (play/rec) default
hw.physmem: 8410640384
Mixer vol      is currently set to  83:83
Mixer pcm      is currently set to 100:100
Mixer speaker  is currently set to 100:100
Mixer mic      is currently set to  67:67
Mixer mix      is currently set to 100:100
Mixer rec      is currently set to  72:72
Mixer igain    is currently set to   0:0
Mixer ogain    is currently set to 100:100
Recording source: mic
```


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## k.jacker (Sep 1, 2017)

Hei,
From my experience, this noise while scrolling is mostly heard from the elektronics of the monitor/TV when the contrast is set to a very high value.
Maybe your computer picks it up. I doubt is has something to do with your sound directly. 

I would at first try to set `mixer mic 0` to see if it's the mic picking it up.

And if that doesn't help or you don't want to turn it off, try lowering contrast and eventually brightness of your screen a little bit.


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## dch (Sep 1, 2017)

sounds awfully like coil whine http://en.community.dell.com/support-forums/laptop/f/3518/t/19995934 interestingly I don't get this any more on my XPS13 using FreeBSD 12.0-CURRENT and drm-next branch which includes the latest Intel graphics drivers. It may also help disabling GPU acceleration within your browser and seeing if that helps too. What FreeBSD release/version are you running?


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## decuser (Sep 3, 2017)

k.jacker, I'll give that a shot and post back.
dch, that sounds interesting. How do I disable GPU acceleration? I'm on FreeBSD 11.1-RELEASE #0 r321309.


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## dch (Sep 3, 2017)

decuser try http://www.tech-recipes.com/rx/5333...mozilla-firefox-chrome-and-internet-explorer/ its basically telling the browser to use the main cpu for all the rendering - slower, but if the noise goes away you can blame your GPU hardware. You *could* see if the very new graphics/drm-next-kmod helps, but you'd need to install 12.0-CURRENT snapshot as its not supported on any release branch yet. At least you can feel happier knowing that it will go away when 12.0 hits the streets.


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