Comment 1 for bug 1000029

I am facing similar issue. My environment is similar to the filer of the bug.

Ubuntu 11.10
Dell Latitude-E5520

It was working fine and now touchpad is very unresponsive.

This happens when the power cable is plugged in. Just like the filer mentioned, the moment the power cable is removed touchpad works fine. Not sure about the first step of the filer. I always run with power connected so the battery never went down and there was no autoshutdown. But steps 3 and 4 are very much reproducible in my system as well.

Note that the touchpad works fine in windows on the same machine.

Just a guess - when power is connected to the laptop, there is a bit of static or vibration in the laptop (especially when you touch it the first time). May be some insulation is not perfect in the dell laptop. It is a new laptop. Not sure if this can affect the touchpad in ubuntu.