Cursor changes its position to any random position itself while typing

Question

I am using Kubuntu 12.04, since Ubuntu 11.04 I am facing this problem.

Most of time my pointer's position changes to any random position itself and it start typing somewhere else and sometime content of last copied lined get pasted itself at current position. This spoils my text, I have to undo every time.

I am very sure that I don't touch my Touchpad.
What can be wrong? Please suggest.

Answer 1

I've had a similar experience on my Dell Vostro laptop, it turns out my touchpad was set to be so sensitive, even just my palm floating a millimetre above it would trigger a click-action. The solution for me was to reduce the sensitivity of the touchpad, but I'm not sure that works on all machines though. Funny thing is, I had the same problem in Ubuntu 11.04 and Windows 7 64-bit and it was very frustrating indeed.

A work-around might be to use a USB mouse (with the touchpad disabled completely, in the BIOS), just to see if it resolves the problem. That way, you can be sure of where the problem is. Once you know it's the touchpad, you can see if tweaking the settings solves the problem.

Answer 2

I've had the same sort of experience. This is what I do to deal with it (it's part of my "install a new Ubuntu version recipe").

Create the /etc/X11/xorg.conf.d directory. In that directory create the file /etc/X11/xorg.conf.d/70-synaptics.conf with the following contents:

Section "InputClass"
    Identifier "touchpad catchall"
    Driver "synaptics"
    MatchIsTouchpad "on"
    Option "PalmDetect" "1"
    Option "PalmMinWidth" "5"
    Option "EmulateTwoFingerMinZ" "5000"
EndSection

Some also use a program that locks the touchpad for a couple of seconds each time a key is pressed--this is not an uncommon problem.

It's the options in the above stanza that do the trick. Your situation may vary because you have different hardware than me. Even if it works for you it may be necessary for you to adjust the values due to a different touchpad/keyboard geometry, different hand size, etc.

Answer 3

I have connected USB mouse to my laptop, because of I am not comfortable with Laptop touch pad. While typing in this setup, I used to touch Touchpad unintentionally. This was changing the typing cursor to some other position. For this the below fix works for me.

%synclient TouchpadOff=1

This command turn off the Touchpad. To enable it again I used below command

%synclient TouchpadOff=0

Thanks,

Shivu