Why is it that my touchpad starts acting funky while the AC adapter is plugged in?

On several of the netbook/laptop computers I’ve owned over the ears, the touchpad becomes “insensitive” to gestures. It’s really damn irritating. You can drag your finger continuously and the mouse will only move slightly. It’s not that big a deal on this Chromebook, but on my old Dell Vostro (two of them actually), the battery kept on dying and the computer would die immediately once you unplugged it. Between Dell’s outrageously expensive replacement batteries/adapters and unscrupulous Chinese replacement battery/adapter vendors, I was always in some sort of electrical purgatory.

I notice this is now happening with my cheapo Chromebook and it’s really pissing me off. At least this computer doesn’t cost $1500. Plus the battery is still good.

Is it some sort of static build up on the computer or something? Maybe screwing up the capacitive effects? I actually have no idea what type of touchpad this thing has. How do most touch pads work these days?

I suspect it’s ac leakage caused by the common-mode RFI filter capacitors in the power supply, which messes up the capacitive trackpad. If you lightly brush your fingers across the surface of the trackpad, can you feel them “hum?”