The drift you noted is a mechanical issue. You proved it with your test of the pressure on the computer.
Almost each time I use my computer my cursor will begin to float across the screen to either the right upper corner or the lower left corner. I usually have the mouse pad turned off and I use my actual mouse – but this still happens. I notice it’s worse when I put any pressure on the computer below the keyboard (but not on the mouse pad) – but it will do this even when I am only using the mouse. I simply use the mouse and move the cursor about and click a few times and the cursor will then, for a while, stay put. I've already replaced the touchpad. Help please

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