Anton,

This might sound like a dumb question, but are you placing the battery in the battery holder properly? The battery should be puched forward and a small moveable plastic piece pops up to hold the battery in place. To dislodge the battery you press down on the piece and it frees the battery.

If the battery is loose and moving I doubt that the camera is drawing any power from the battery in the grip and is probably drawing from the "in camera" battery.

Tom

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