I upgraded to Ubuntu 9.04 recently and had experienced a weird keyboard input problem. Sometimes a certain program stops responding to any keyboard inputs for a short period of time, then all of a sudden all the keys I've pressed jumps out at once. It only happens to one program at a time. The programs I've had this issue with include Firefox, Emacs 23.1, konsole, eclipse. It happens frequently, like three to four times in an hour. I thought this might be a Ubuntu issue, so I switched to Fedora 11. And I have the same problem. So I'm not sure which part of the system is responsible for this bug, KDE 4.3, the kernel, X, or some other program. Any hints?

Thanks.

Does it correspond to disk access (watch the disk access light when it is not responding)? How much memory do you have?

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"Tell me, Mr. Anderson, what good is a keyboard when you are unable to type"

It doesn't seem to be doing a lot of disk IOs at that time. I have 2GBs of physical ram and 1GB of swap space.

One more thing I've noticed is that when I'm compiling huge C++ projects, which uses almost all of the physical memory, random characters start to appear when I try to type in Pidgin. But this has been observed in Pidgin only so far.

Try to use top to see what is eating resources at the moment the problem occurs.

I tried using top, nothing seemed to be eating a lot of the resources. Everything's pretty responsive except for the program that stopped accepting inputs at that moment.

Hi,
although this topic is pretty old - I have exactly the same problem on ubuntu lucid. Did you ever found any solution? It really drives me crazy to wait for that lag to be over while writing...

I also checked for applications having heavy load but found nothing. I use a Logitech wireless (unified wireless) keyboard but a normal mouse with cable and assumed that something goes wrong with the driver for that wireless USB device... I run Windows (XP and 7) on this machine, too but without any keyboard problems.

Very thankfull for any suggenstions...