JBL offers a variety of in-ear and over-the-ear headphones that let you connect to your MP3 player wirelessly with Bluetooth or via an audio cable. If you hear sound from only one side of the headphones, the Bluetooth transceiver or audio cable is most likely not properly connected. Problems also occur when the headphones move out of range of the Bluetooth transceiver.
Check Bluetooth Transceiver Connection
If you hear sound through one side of the headphones, but not the other, check the Bluetooth transceiver connection. The transceiver connects directly to your MP3 player, allowing the headphones to communicate with it wirelessly. Disconnect the devices and pair them by pressing the "On" button on the headphones. When the LED light flashes, connect the transceiver to the iPod. The transceiver blinks for a few seconds. When the blinking stops, the devices are paired.
Check Audio Cable Connection
Some JBL headphones work by connecting to your MP3 player via audio cable. If you do not connect the audio cable correctly, the headphones may emit sound through only one side. Ensure that the 3.5 mm mini stereo jack is connected securely to your MP3 player. If you have Bluetooth headphones that can also connect with an audio cable, connect the mini USB end of the cable to the charge port of the headphones.
Move within Transceiver Range
JBL Bluetooth headphones must remain in range of the transceiver to function properly. If the sound starts to drop in and out, or you only hear audio through one side, move closer to the MP3 player and the transceiver. The headphones have difficulty connecting to the transceiver through metal objects and walls. Eliminate as many obstructions as possible to get the best connection. If you lose the connection entirely, press the "Play/Pause" button on the headphones to reconnect.
Connecting the JBL headphones to your MP3 player with Bluetooth drains the headphone's battery power. When the headphones have a low battery, an LED blinks blue and the headphones emit a low warning tone that prompts you to charge the battery. When the battery is low, the headphones do not work as normal. Sound may come through only one side of the headphones until the battery runs out completely. Charge the headphones with the included AC adapter. This takes about three hours.