Could be a faulty phone or the aux port on your car could be the issue. The best way to confirm is to use your phone plugged into a different device/vehicle aux port and a different phone on your car's aux port. Best wishes.
Hello, I can use bluetooth devices fine, but when I try to plug my phone into my cars aux cord it sounds like there is an added reverb type effect, like after the snares and hi hats there's a fading out type of sound. I'm wondering what is the cause of this? And how can I get rid of it!?

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