Original post by: Mike Ulloa ,
SOLUTION - After all that has been said I would like to suggest the most common cause of this issue. This issue will regularly occur when the charging port flex connector is replaced. In this case the crackling may be caused by a grounding problem between the top of the charging port flex connector and the metal screw panel. The top of the connector must be insulated from the screw panel that secures the ribbon cable onto the logic board. This can be accomplished with a small piece of electrical tape.