hello my name is ***** ***** I am a Korg technician. I think you are speaking of the connector where the power comes in. If that is correct you probably have one of three problems. any of which you would have to open the unit and use a souldering iron. (1) the connector inside is souldered to the board inside. the most common problem is the soulder has broken louse and will have to be resouldered. (2) the connector is broken and will have to be replaced. (3) the board the connector is souldered to is broken and will have to be replaced.
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