# Mouse skipping vertically in some games

## fau

This is a strange one: Some time ago my mouse started skipping vertically in quake. I'll try to describe it as good as I can. It starts after few minutes of playing. At first these are small and rare skips, but when I play longer they are getting larger to the point where it goes all the way up/down non-stop. It seems that not moving mouse calms it down for a while.

The mouse had 7 years so I thought it's broken and got a new one (microsoft wheel mouse optical, I know it's m$ but this is by far the best mouse I've seen  :Smile:  ). It didn't help at all. Next thought was that usb port was overheating. It reminded me that I actually have an windows partition, so I booted it, played for a while and.. nothing, no skipping at all. It made me very suspicious so I've made a few tests, here they are:

windows no skipping at all

linux desktop (xmonad) - no skipping. I've spend like 15 minutes drawing lines in gimp

linux quakelive - skipping (also with in_mouse 2 which should theoreticaly take raw mouse input)

linux quake3 - the same

linux teewars - it skips, but to a lesser extend and less often that in quakes (how it is different than quakes? I used higher sensitivity in teewars so I wasn't moving my mouse so much and with such high speed. I have a feeling that it matters)

linux some random fps game with very high sensitivity - no skiping

linux starcraft under wine (medium sensitivity, like in teewars) - no skipping (!)

I've also tested it with older kernel (2.6.33) and the results are the same.

I suspect that the reason for this might be some evdev/sdl/something else update, but older versions aren't in portage and I don't feel like spending few hours downgrading them manually to find out that it wasn't the case.

I'll test it with gpm now, but I'm running out of ideas what it may be. Do you have any?

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## Hu

If you can recall when this started happening, you could review /var/log/emerge.log to see what packages were installed around that time.  That might give you a hint about which package to try downgrading.

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## fau

It's hard to tell as I wasn't playing very often and it started like month ago. Which packages would you suggest downgrading? xinput? evdev? Older versions aren't in portage. I'm going to try with livecd tomorrow, but even if it works it wont give me any hint where is the problem.

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## PaulBredbury

The common culprit is DGA. See thread regarding:

in_dgamouse = 0

for no dga input.

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## fau

I've tested all possible settings with in_mouse and in_dgamouse, disabled dga and nothing helped. Also noticed that in_restart makes things calm down for few minutes.

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## darklegion

Tried disabling mouse acceleration?

```

xset m 0 0 

```

I should note I play Quake Live with and without "in_mouse 2" and I've never had an issue like that, even when I had X11 mouse acceleration enabled.

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