I experienced this on my iPhone, the problem only exists when power cable is connected and charging.
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I experienced this on my iPhone just 1 hour ago, the problem only exists when power cable is connected and charging.
If disconnected from powersource, everything is smooth again.
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The comment of Prashanth above is correct, something related to USB charging port. Maybe the smartphone was presssed hard on your pocket or was dropped which caused the problem.
I experienced this on my iPhone, the problem only exists when power cable is connected and charging.
If disconnected from powersource, everything is smooth again.