Originally Posted by
GraphiteGhost
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Is your stereo the Infinity OEM unit? Does all speakers respond to the contours you select if the Infinity is OEM? Depending on your results to these questions then it might be an added woofer or amp that was installed in the lower hatch area.
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Yes it's the OEM Infinity unit. I think the previous owner installed like a woofer in the trunk but sold the car without it. Thank you for the answers guys.