Ghost touches even when unplugged

Hi everyone,

My Android tablet (ASUS MeMO Pad FHD 10 ME302C) is showing ghost touches either when plugged in or plugged out, no matter if the battery is lightly, half or fully charged.

I enabled "Show touches" and "Pointer location" in "Developer options" and the behavior is as follows:

• when tablet boots up, little to no ghost touches
• after just a few seconds, it starts ghost touching all over the screen
• when I rotate the tablet at 90/180/270/360°, it seems to me the ghost touches are even more severe

I also tried the following actions:

• cleaning up the tablet with a dry cloth
• resetting the tablet to factory defaults
• removing the sd card
• charging the tablet with several AC adapters
• letting the battery ran out and charging it again
• opening the tablet and disconnect the digitizer (the ghost touches stop but so does the whole touch screen)
• pluging back in the digitizer and thus, "force" a touch screen calibration (shows a "ASUS Calibration in progress" dialog)
• opening the tablet and disconnect/reconnect the battery
• opening the tablet and disconnect the motherboard, battery and speakers and plug them back in

Unfortunately, the issue is still present and I am asking for advice. Should I try replacing the digitizer, battery and/or screen and, if so, is there any "guarantee" that it will resolve the ghost touches? Or should I resign myself and simply buy another tablet?

Thanks anyone for your time and advice.