I've just bought this second hand Ibanez classical and when the open A is played the bridge rattles. It also happens on the 12th fret of most strings.

I've taken pictures incase anyone can spot a problem - would a string change to lower gauge fix it?


Update: the problem has been located, the battery pack is vibrating when batteries are inside. If batteries are taken out or pressure is put on the battery pack, the vibration goes. Any tips for a permanent fix?
Put some tape on it or fill the space with a folded piece of paper

Ibanez ARX 350
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Ibanez TS9
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DRIVE Elite straight 412