Hello! I have a strange problem.
My laptop: Acer C720 chromebook
I installed johnlewis bios and original ubuntu 16.04 LTS (+ 14.04.4 LTS, and 14.10 (as I remember) nonLTS)
Everythinh is fine, but I have 1 strange big problem with touchpad.

When I put my laptop on a table or any other flat surface touchpad stops working.
If I keep my laptom on my laps or in my hand, everything works. If I put the laptop on the full back cover, touchpad stops working.
Touchpad is not responding. Sometimes, the cursor begins to move very poorly performing many clicks.

I have checked the hardware.This is no problem. I installed windows 10 (thx coolstar) and touchpad worked everywhere). Also, touchpad worked with original Chrome OS.

ONLY on Ubuntu touchpad doesn't work when I put my laptop.

I need ubuntu. I can make a video if it necessary. I can send every log, just ask me.

Please help me solve my problem! If I need to post this topic in another place, dear moderator, please, replace it!