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Hi to anyone who can help , i have purchased two rft 1081's both used .
the first one works great, the other arrived and was rattling inside , so i unscrewed the speaker and there was a coil type of roll connected to the wiring unglued from the corner along with a metal solid tube around 8 cm long and 1.5 cm wide rolling around , the first one has not got this in and is empty and works great , can someone explain if i need this and what its for please.