Trackpad delay at first touch, intermittent

Not sure if this is an OS issue or hardware. Using Ubuntu 21.0, trackpad would work great about 75% of the time. By that, I mean, place fingers on, instantly recognized placement, able to move cursor immediately. But then 25% of the time, upon touching, there is a 1 to 2 second delay before the touchpad recognizes it is being touched and takes about that long before the cursor will start to move around. BIOS is up to date. Thoughts on what may cause this issue?

just a guess but it sounds like some kind of power management/power saving?

Come to think of it, the display also tends to lighten and darken for no apparent reason. It’s like it is trying to respond and adjust to ambient light. This is corroborated by looking at the display settings and you can watch the toggle bar move left and right in real-time while the display slightly lightens and darkens. Not sure if that’s related to the trackpad or not, but it is another annoying oddity.

There is an ambient light sensor which can adjust the display brightness automatically, but this is usually in Windows. In Ubuntu I don’t know where the setting would be to turn it off.

Regarding the trackpad, have you disabled PS/2 emulation in the BIOS?

Yep. Disabled the PS/2. Saw that as a workaround for a different issue someone posted, but it didn’t fix this one.

In gnome, at least, there is an option is Settings/Power for “Automatic Screen Brightness” (which selects whether to adjust to surrounding light). Turning that off made the changing screen backlight intensity go away for me.


I see this behavior when using Wayland based desktop environment when PSR is enabled. In X11 or with PSR disabled, I do not see the “first touch delay” you are describing. Could you try X11 session, and/or making sure PSR is off?