Weird touchscreen response while charging iPhone 4.?

I am having the same issue on my iPhone 4S. While charging, the touch screen will perform wildly inaccurately. I will touch one spot on the screen and an entirely different section of the screen will react.

I bought this in to the apple store and got my phone replaced under warranty.

Still, my new phone is having the exact same problem. This is incredibly frustrating, especially b/c I try not to charge my battery until it is very low (as you should with LI batteries). This often means I'm charging my phone during the work day and cannot use it b/c of the screen issue.

Could it be a software issue since I am experiencing this on two different phones?

There is a faulty ground on your setup, allowing a static or dynamic charge to build up on your device, and making the capacitive touch sensor go haywire. While it's charging, do you feel a slight buzzing when touching the phone's metal parts? If so, use a different plug or charging wire.

REMOVE SCREEN PROTECTOR AND ANY IPHONE CASE !😁

NOT WHEN THE CASE IS DESIGNED BY APPLE IN CALIFORNIA!!!!!!!!!!