To pair a bluetooth device with the radio, turn on the Bluetooth function of the device. Then press the SRC (source) button on the receiver. Select BT Audio or BT Phone, depending on the device you want to pair with the radio. Use the up/down arrows to select New Device and press the down arrow. Select Open and then press the down arrow. Then enter the PIN by using the left/right arrows to select a digit and turning the volume knob until the correct digit is entered. (For some devices, you need to enter a specific PIN. Consult that device's manual.) Press the down arrow to set the PIN. Enter the PIN in the device you are pairing to the receiver (if it doesn't have a required PIN). Wait for the message "Connected" to appear.
To use the device in the future, press SRC and choose the appropriate Bluetooth type. Then use the right/left arrows to select the registered device. Press the down arrow and then use the right/left arrows to select Connect and press the down arrow. (See the manual, link below, for setting the autoconnect or autoanswer.)
To adjust the sound system balance, press and hold Menu to open the menu and then turn the volume knob to Audio. Press the center of the Volume knob. Then navigate to balance and adjust the unit as needed.
The manual for the KD-HDR20 is available from JVC on the product support page: http://support.jvc.com/consumer/product.jsp?archive=true&pathId=54&modelId=MODL028465
. The direct link to the instruction manual is http://resources.jvc.com/Resources/00/01/14/LVT1960-001A.pdf
I hope this helps.