JVC KD-X320BT bluetooth problem - solution: update firmware for system and bluetooth (short version)
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KDX320BT KDX320BTS KDX220 KDX12x and others JVC Units
JVC firmware: JVC Kenwood firmware: http://www.jvc.net/cs/car/firmware/ JVC / Kenwood system / bluetooth firmware how to fix JVC KENWOOD BLUETOOTH PROBLEM