How to Troubleshoot a JBL PC Speaker for Distorted Sound ?

JBL computer speakers attach to your computer via the audio output jack and provide better sound quality than the internal computer speaker. Most JBL computer speaker systems are active or self-powered, meaning that they must be plugged into an electrical outlet in order to amplify the audio signal. Audio distortion is characterized by static, crackling or hissing sounds and can be the result of interference, overdrive (when the signal is too "hot"), faulty hardware or a corrupted sound file.

Instructions :-

1- Check for interference by turning off your monitor and listening for distortion. If the noise is eliminated by turning off the monitor, move speakers and speaker cables away from the monitor.

2-Examine the speaker cable connections. Ensure that the speakers are plugged into the appropriate audio jack(s) on the back of the computer. JBL speaker cables are color coded and the green-tipped cable should be plugged into the green primary audio output jack on your sound card. Cables should be plugged in snugly and completely. If there is any doubt about the connection, unplug and then plug the cable into the jack again.

 3-Adjust the volume of the sound card. If the output signal is over-driven (the audio signal is too "hot") this may cause distortion. Double-click the speaker icon in the bottom right corner of your computer screen to bring up the audio levels/volume control panel. Bring down the primary audio volume slider by clicking on it and dragging downward until the slider is midway between the maximum and minimum settings. Adjust the speaker volume and listen for distortion.

4-Adjust the treble and bass knobs on the subwoofer, setting them back at the central/nominal midway setting. Many JBL computer speaker systems include a powered subwoofer for added bass response. If the subwoofer is being overpowered by the bass signal and causing distortion, this will eliminate it.

5-Test the JBL speakers through another audio source. Plug the green-tipped speaker cable into another computer, a laptop or the headphone jack on a portable CD player or digital media device. Turn the volume down all the way and play an audio file, bringing the speaker volume up until the sound is at a comfortable listening volume. If distortion is still present, the problem may be the JBL speakers or speaker cables. If the distortion is gone, the problem is most likely with the original computer's sound card.